Auto merge of #27893 - servo:dependabot/cargo/futures-executor-0.3.8, r=jdm

Bump futures-executor from 0.3.5 to 0.3.8

Bumps [futures-executor](https://github.com/rust-lang/futures-rs) from 0.3.5 to 0.3.8.
<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>0.3.8</h2>
<ul>
<li>Switch proc-macros to use native <code>#[proc_macro]</code> at Rust 1.45+ (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2243">#2243</a>)</li>
<li>Add <code>WeakShared</code> (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2169">#2169</a>)</li>
<li>Add <code>TryStreamExt::try_buffered</code> (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2245">#2245</a>)</li>
<li>Add <code>StreamExt::cycle</code> (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2252">#2252</a>)</li>
<li>Implemented <code>Clone</code> for <code>stream::{Empty, Pending, Repeat, Iter}</code> (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2248">#2248</a>, <a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2252">#2252</a>)</li>
<li>Fix panic in some <code>TryStreamExt</code> combinators (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2250">#2250</a>)</li>
</ul>
<h2>0.3.7</h2>
<ul>
<li>Fixed unsoundness in <code>MappedMutexGuard</code> (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2240">#2240</a>)</li>
<li>Re-exported <code>TakeUntil</code> (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2235">#2235</a>)</li>
<li>futures-test: Prevent double panic in <code>panic_waker</code> (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2236">#2236</a>)</li>
</ul>
<h2>0.3.6</h2>
<ul>
<li>Fixed UB due to missing 'static on <code>task::waker</code> (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2206">#2206</a>)</li>
<li>Added <code>AsyncBufReadExt::fill_buf</code> (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2225">#2225</a>)</li>
<li>Added <code>TryStreamExt::try_take_while</code> (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2212">#2212</a>)</li>
<li>Added <code>is_connected_to</code> method to <code>mpsc::{Sender, UnboundedSender}</code> (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2179">#2179</a>)</li>
<li>Added <code>is_connected_to</code> method to <code>oneshot::Sender</code> (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2158">#2158</a>)</li>
<li>Implement <code>FusedStream</code> for <code>FuturesOrdered</code> (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2205">#2205</a>)</li>
<li>Fixed documentation links</li>
<li>Improved documentation</li>
<li>futures-test: Added <code>track_closed</code> method to <code>AsyncWriteTestExt</code> and <code>SinkTestExt</code> (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2159">#2159</a>)</li>
<li>futures-test: Implemented more traits for <code>InterleavePending</code> (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2208">#2208</a>)</li>
<li>futures-test: Implemented more traits for <code>AssertUnmoved</code> (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2208">#2208</a>)</li>
</ul>
</blockquote>
</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>0.3.8 - 2020-11-04</h1>
<ul>
<li>Switch proc-macros to use native <code>#[proc_macro]</code> at Rust 1.45+ (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2243">#2243</a>)</li>
<li>Add <code>WeakShared</code> (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2169">#2169</a>)</li>
<li>Add <code>TryStreamExt::try_buffered</code> (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2245">#2245</a>)</li>
<li>Add <code>StreamExt::cycle</code> (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2252">#2252</a>)</li>
<li>Implemented <code>Clone</code> for <code>stream::{Empty, Pending, Repeat, Iter}</code> (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2248">#2248</a>, <a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2252">#2252</a>)</li>
<li>Fix panic in some <code>TryStreamExt</code> combinators (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2250">#2250</a>)</li>
</ul>
<h1>0.3.7 - 2020-10-23</h1>
<ul>
<li>Fixed unsoundness in <code>MappedMutexGuard</code> (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2240">#2240</a>)</li>
<li>Re-exported <code>TakeUntil</code> (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2235">#2235</a>)</li>
<li>futures-test: Prevent double panic in <code>panic_waker</code> (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2236">#2236</a>)</li>
</ul>
<h1>0.3.6 - 2020-10-06</h1>
<ul>
<li>Fixed UB due to missing 'static on <code>task::waker</code> (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2206">#2206</a>)</li>
<li>Added <code>AsyncBufReadExt::fill_buf</code> (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2225">#2225</a>)</li>
<li>Added <code>TryStreamExt::try_take_while</code> (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2212">#2212</a>)</li>
<li>Added <code>is_connected_to</code> method to <code>mpsc::{Sender, UnboundedSender}</code> (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2179">#2179</a>)</li>
<li>Added <code>is_connected_to</code> method to <code>oneshot::Sender</code> (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2158">#2158</a>)</li>
<li>Implement <code>FusedStream</code> for <code>FuturesOrdered</code> (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2205">#2205</a>)</li>
<li>Fixed documentation links</li>
<li>Improved documentation</li>
<li>futures-test: Added <code>track_closed</code> method to <code>AsyncWriteTestExt</code> and <code>SinkTestExt</code> (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2159">#2159</a>)</li>
<li>futures-test: Implemented more traits for <code>InterleavePending</code> (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2208">#2208</a>)</li>
<li>futures-test: Implemented more traits for <code>AssertUnmoved</code> (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2208">#2208</a>)</li>
</ul>
</blockquote>
</details>
<details>
<summary>Commits</summary>
<ul>
<li><a href="bde29dad82"><code>bde29da</code></a> Release 0.3.8</li>
<li><a href="ed0c997e86"><code>ed0c997</code></a> Remove needless borrows and method calls (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2259">#2259</a>)</li>
<li><a href="f521ecc3be"><code>f521ecc</code></a> Use HTTPS (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2258">#2258</a>)</li>
<li><a href="a570781fed"><code>a570781</code></a> Add StreamExt::cycle (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2252">#2252</a>)</li>
<li><a href="1fa794a593"><code>1fa794a</code></a> Use Self keyword instead of concrete type name (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2251">#2251</a>)</li>
<li><a href="90b4a8e6cb"><code>90b4a8e</code></a> Add TryStreamExt::try_buffered (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2245">#2245</a>)</li>
<li><a href="76672516d3"><code>7667251</code></a> Fix panic in some TryStreamExt combinators (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2250">#2250</a>)</li>
<li><a href="310fd0d608"><code>310fd0d</code></a> impl Clone for stream::{Empty, Pending, Repeat} (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2248">#2248</a>)</li>
<li><a href="e363f1839f"><code>e363f18</code></a> Fix clippy::unnecessary_cast warning</li>
<li><a href="4122f3d5af"><code>4122f3d</code></a> Use only_hack_old_rustc for proc_macro_hack (<a href="https://github-redirect.dependabot.com/rust-lang/futures-rs/issues/2243">#2243</a>)</li>
<li>Additional commits viewable in <a href="https://github.com/rust-lang/futures-rs/compare/0.3.5...0.3.8">compare view</a></li>
</ul>
</details>
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Cargo.lock

@@ -1837,9 +1837,9 @@ dependencies = [
 
 [[package]]
 name = "futures-executor"
-version = "0.3.5"
+version = "0.3.8"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "10d6bb888be1153d3abeb9006b11b02cf5e9b209fda28693c31ae1e4e012e314"
+checksum = "4caa2b2b68b880003057c1dd49f1ed937e38f22fcf6c212188a121f08cf40a65"
 dependencies = [
  "futures-core",
  "futures-task",