Auto merge of #28764 - servo:dependabot/cargo/futures-executor-0.3.21, r=jdm

Bump futures-executor from 0.3.8 to 0.3.21

Bumps [futures-executor](https://github.com/rust-lang/futures-rs) from 0.3.8 to 0.3.21.
<details>
<summary>Release notes</summary>
<p><em>Sourced from <a href="https://github.com/rust-lang/futures-rs/releases">futures-executor's releases</a>.</em></p>
<blockquote>
<h2>0.3.21</h2>
<ul>
<li>Fix potential data race in <code>FlattenUnordered</code> that introduced in 0.3.20 (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2566">#2566</a>)</li>
</ul>
<h2>0.3.20</h2>
<ul>
<li>Fix stacked borrows violations when <code>-Zmiri-tag-raw-pointers</code> is enabled. This raises MSRV of <code>futures-task</code> to 1.45. (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2548">#2548</a>, <a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2550">#2550</a>)</li>
<li>Change <code>FuturesUnordered</code> to respect yielding from future (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2551">#2551</a>)</li>
<li>Add <code>StreamExt::{flatten_unordered, flat_map_unordered}</code> (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2083">#2083</a>)</li>
</ul>
<h2>0.3.19</h2>
<ul>
<li>Remove unstable <code>read-initializer</code> feature (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2534">#2534</a>)</li>
<li>Fix panic in <code>FuturesUnordered</code> (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2535">#2535</a>)</li>
<li>Fix compatibility issue with <code>FuturesUnordered</code> and tokio's cooperative scheduling (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2527">#2527</a>)</li>
<li>Add <code>StreamExt::count</code> (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2495">#2495</a>)</li>
</ul>
<h2>0.3.18</h2>
<ul>
<li>Fix unusable <code>Sink</code> implementation on <code>stream::Scan</code> (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2499">#2499</a>)</li>
<li>Make <code>task::noop_waker_ref</code> available without <code>std</code> feature (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2505">#2505</a>)</li>
<li>Add async <code>LineWriter</code> (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2477">#2477</a>)</li>
<li>Remove dependency on <code>proc-macro-hack</code>. This raises MSRV of utility crates to 1.45. (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2520">#2520</a>)</li>
</ul>
<h2>0.3.17</h2>
<ul>
<li>Use <code>FuturesOrdered</code> in <code>join_all</code> (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2412">#2412</a>)</li>
<li>Add <code>{future, stream}::poll_immediate</code> (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2452">#2452</a>)</li>
<li>Add <code>stream_select!</code> macro (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2262">#2262</a>)</li>
<li>Implement <code>Default</code> for <code>OptionFuture</code> (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2471">#2471</a>)</li>
<li>Add <code>Peekable::{peek_mut, poll_peek_mut}</code> (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2488">#2488</a>)</li>
<li>Add <code>BufReader::seek_relative</code> (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2489">#2489</a>)</li>
</ul>
<h2>0.3.16</h2>
<ul>
<li>Add <code>TryStreamExt::try_chunks</code> (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2438">#2438</a>)</li>
<li>Add <code>StreamExt::{all, any}</code> (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2460">#2460</a>)</li>
<li>Add <code>stream::select_with_strategy</code> (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2450">#2450</a>)</li>
<li>Update to new <code>io_slice_advance</code> interface (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2454">#2454</a>)</li>
</ul>
<h2>0.3.15</h2>
<ul>
<li>Use <code>#[proc_macro]</code> at Rust 1.45+ to fix an issue where proc macros don't work with rust-analyzer (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2407">#2407</a>)</li>
<li>Support targets that do not have atomic CAS on stable Rust (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2400">#2400</a>)</li>
<li>futures-test: Add async <code>#[test]</code> function attribute (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2409">#2409</a>)</li>
<li>Add <code>stream::abortable</code> (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2410">#2410</a>)</li>
<li>Add <code>FuturesUnordered::clear</code> (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2415">#2415</a>)</li>
<li>Implement <code>IntoIterator</code> for <code>FuturesUnordered</code> (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2423">#2423</a>)</li>
<li>Implement <code>Send</code> and <code>Sync</code> for <code>FuturesUnordered</code> iterators (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2416">#2416</a>)</li>
<li>Make <code>FuturesUnordered::iter_pin_ref</code> public (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2423">#2423</a>)</li>
<li>Add <code>SelectAll::clear</code> (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2430">#2430</a>)</li>
<li>Add <code>SelectAll::{iter, iter_mut}</code> (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2428">#2428</a>)</li>
<li>Implement <code>IntoIterator</code> for <code>SelectAll</code> (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2428">#2428</a>)</li>
<li>Implement <code>Clone</code> for <code>WeakShared</code> (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2396">#2396</a>)</li>
</ul>
<h2>0.3.14</h2>
<ul>
<li>Add <code>future::SelectAll::into_inner</code> (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2363">#2363</a>)</li>
</ul>
<!-- raw HTML omitted -->
</blockquote>
<p>... (truncated)</p>
</details>
<details>
<summary>Changelog</summary>
<p><em>Sourced from <a href="https://github.com/rust-lang/futures-rs/blob/master/CHANGELOG.md">futures-executor's changelog</a>.</em></p>
<blockquote>
<h1>0.3.21 - 2022-02-06</h1>
<ul>
<li>Fix potential data race in <code>FlattenUnordered</code> that introduced in 0.3.20 (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2566">#2566</a>)</li>
</ul>
<h1>0.3.20 - 2022-02-06</h1>
<p>NOTE: This release has been yanked due to a bug fixed in 0.3.21.</p>
<ul>
<li>Fix stacked borrows violations when <code>-Zmiri-tag-raw-pointers</code> is enabled. This raises MSRV of <code>futures-task</code> to 1.45. (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2548">#2548</a>, <a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2550">#2550</a>)</li>
<li>Change <code>FuturesUnordered</code> to respect yielding from future (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2551">#2551</a>)</li>
<li>Add <code>StreamExt::{flatten_unordered, flat_map_unordered}</code> (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2083">#2083</a>)</li>
</ul>
<h1>0.3.19 - 2021-12-18</h1>
<ul>
<li>Remove unstable <code>read-initializer</code> feature (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2534">#2534</a>)</li>
<li>Fix panic in <code>FuturesUnordered</code> (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2535">#2535</a>)</li>
<li>Fix compatibility issue with <code>FuturesUnordered</code> and tokio's cooperative scheduling (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2527">#2527</a>)</li>
<li>Add <code>StreamExt::count</code> (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2495">#2495</a>)</li>
</ul>
<h1>0.3.18 - 2021-11-23</h1>
<p>NOTE: This release has been yanked. See <a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2529">#2529</a> for details.</p>
<ul>
<li>Fix unusable <code>Sink</code> implementation on <code>stream::Scan</code> (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2499">#2499</a>)</li>
<li>Make <code>task::noop_waker_ref</code> available without <code>std</code> feature (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2505">#2505</a>)</li>
<li>Add async <code>LineWriter</code> (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2477">#2477</a>)</li>
<li>Remove dependency on <code>proc-macro-hack</code>. This raises MSRV of utility crates to 1.45. (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2520">#2520</a>)</li>
</ul>
<h1>0.3.17 - 2021-08-30</h1>
<ul>
<li>Use <code>FuturesOrdered</code> in <code>join_all</code> (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2412">#2412</a>)</li>
<li>Add <code>{future, stream}::poll_immediate</code> (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2452">#2452</a>)</li>
<li>Add <code>stream_select!</code> macro (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2262">#2262</a>)</li>
<li>Implement <code>Default</code> for <code>OptionFuture</code> (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2471">#2471</a>)</li>
<li>Add <code>Peekable::{peek_mut, poll_peek_mut}</code> (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2488">#2488</a>)</li>
<li>Add <code>BufReader::seek_relative</code> (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2489">#2489</a>)</li>
</ul>
<h1>0.3.16 - 2021-07-23</h1>
<ul>
<li>Add <code>TryStreamExt::try_chunks</code> (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2438">#2438</a>)</li>
<li>Add <code>StreamExt::{all, any}</code> (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2460">#2460</a>)</li>
<li>Add <code>stream::select_with_strategy</code> (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2450">#2450</a>)</li>
<li>Update to new <code>io_slice_advance</code> interface (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2454">#2454</a>)</li>
</ul>
<h1>0.3.15 - 2021-05-11</h1>
<ul>
<li>Use <code>#[proc_macro]</code> at Rust 1.45+ to fix an issue where proc macros don't work with rust-analyzer (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2407">#2407</a>)</li>
<li>Support targets that do not have atomic CAS on stable Rust (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2400">#2400</a>)</li>
<li>futures-test: Add async <code>#[test]</code> function attribute (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2409">#2409</a>)</li>
<li>Add <code>stream::abortable</code> (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2410">#2410</a>)</li>
</ul>
<!-- raw HTML omitted -->
</blockquote>
<p>... (truncated)</p>
</details>
<details>
<summary>Commits</summary>
<ul>
<li><a href="fc1e325021"><code>fc1e325</code></a> Release 0.3.21</li>
<li><a href="20279ebbfc"><code>20279eb</code></a> <code>FlattenUnordered</code>: improve wakers behavior (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2566">#2566</a>)</li>
<li><a href="75dca5ae7f"><code>75dca5a</code></a> Fix MSRV in futures-task readme</li>
<li><a href="55281c8c8d"><code>55281c8</code></a> Release 0.3.20</li>
<li><a href="591b982af8"><code>591b982</code></a> Redefine executor and compat modules in futures crate (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2564">#2564</a>)</li>
<li><a href="94b508bfcb"><code>94b508b</code></a> Basic <code>StreamExt::{flatten_unordered, flat_map_unordered}</code> impls (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2083">#2083</a>)</li>
<li><a href="dca16fafa5"><code>dca16fa</code></a> Do not auto-create PR on fork</li>
<li><a href="a9795a9243"><code>a9795a9</code></a> Automatically creates PR when no_atomic_cas.rs needs to be updated</li>
<li><a href="4841888d68"><code>4841888</code></a> Update comments in build scripts</li>
<li><a href="85706b6d67"><code>85706b6</code></a> Clean up ci/no_atomic_cas.sh</li>
<li>Additional commits viewable in <a href="https://github.com/rust-lang/futures-rs/compare/0.3.8...0.3.21">compare view</a></li>
</ul>
</details>
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Cargo.lock

@@ -1864,9 +1864,9 @@ checksum = "0c09fd04b7e4073ac7156a9539b57a484a8ea920f79c7c675d05d289ab6110d3"
 
 [[package]]
 name = "futures-executor"
-version = "0.3.8"
+version = "0.3.21"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "4caa2b2b68b880003057c1dd49f1ed937e38f22fcf6c212188a121f08cf40a65"
+checksum = "9420b90cfa29e327d0429f19be13e7ddb68fa1cccb09d65e5706b8c7a749b8a6"
 dependencies = [
  "futures-core",
  "futures-task",