Auto merge of #27798 - servo:dependabot/cargo/regex-1.4.2, r=jdm

Bump regex from 1.3.9 to 1.4.2

Bumps [regex](https://github.com/rust-lang/regex) from 1.3.9 to 1.4.2.
<details>
<summary>Changelog</summary>
<p><em>Sourced from <a href="https://github.com/rust-lang/regex/blob/master/CHANGELOG.md">regex's changelog</a>.</em></p>
<blockquote>
<h1>1.4.2 (2020-11-01)</h1>
<p>This is a small bug fix release that bans <code>\P{any}</code>. We previously banned empty
classes like <code>[^\w\W]</code>, but missed the <code>\P{any}</code> case. In the future, we hope
to permit empty classes.</p>
<ul>
<li>[BUG <a href="https://github-redirect.dependabot.com/rust-lang/regex/issues/722">#722</a>](<a href="https://github-redirect.dependabot.com/rust-lang/regex/issues/722">rust-lang/regex#722</a>):
Ban <code>\P{any}</code> to avoid a panic in the regex compiler. Found by OSS-Fuzz.</li>
</ul>
<h1>1.4.1 (2020-10-13)</h1>
<p>This is a small bug fix release that makes <code>\p{cf}</code> work. Previously, it would
report &quot;property not found&quot; even though <code>cf</code> is a valid abbreviation for the
<code>Format</code> general category.</p>
<ul>
<li>[BUG <a href="https://github-redirect.dependabot.com/rust-lang/regex/issues/719">#719</a>](<a href="https://github-redirect.dependabot.com/rust-lang/regex/issues/719">rust-lang/regex#719</a>):
Fixes bug that prevented <code>\p{cf}</code> from working.</li>
</ul>
<h1>1.4.0 (2020-10-11)</h1>
<p>This releases has a few minor documentation fixes as well as some very minor
API additions. The MSRV remains at Rust 1.28 for now, but this is intended to
increase to at least Rust 1.41.1 soon.</p>
<p>This release also adds support for OSS-Fuzz. Kudos to
<a href="https://github.com/DavidKorczynski">@DavidKorczynski</a>
for doing the heavy lifting for that!</p>
<p>New features:</p>
<ul>
<li>[FEATURE <a href="https://github-redirect.dependabot.com/rust-lang/regex/issues/649">#649</a>](<a href="https://github-redirect.dependabot.com/rust-lang/regex/issues/649">rust-lang/regex#649</a>):
Support <code>[</code>, <code>]</code> and <code>.</code> in capture group names.</li>
<li>[FEATURE <a href="https://github-redirect.dependabot.com/rust-lang/regex/issues/687">#687</a>](<a href="https://github-redirect.dependabot.com/rust-lang/regex/issues/687">rust-lang/regex#687</a>):
Add <code>is_empty</code> predicate to <code>RegexSet</code>.</li>
<li>[FEATURE <a href="https://github-redirect.dependabot.com/rust-lang/regex/issues/689">#689</a>](<a href="https://github-redirect.dependabot.com/rust-lang/regex/issues/689">rust-lang/regex#689</a>):
Implement <code>Clone</code> for <code>SubCaptureMatches</code>.</li>
<li>[FEATURE <a href="https://github-redirect.dependabot.com/rust-lang/regex/issues/715">#715</a>](<a href="https://github-redirect.dependabot.com/rust-lang/regex/issues/715">rust-lang/regex#715</a>):
Add <code>empty</code> constructor to <code>RegexSet</code> for convenience.</li>
</ul>
<p>Bug fixes:</p>
<ul>
<li>[BUG <a href="https://github-redirect.dependabot.com/rust-lang/regex/issues/694">#694</a>](<a href="https://github-redirect.dependabot.com/rust-lang/regex/issues/694">rust-lang/regex#694</a>):
Fix doc example for <code>Replacer::replace_append</code>.</li>
<li>[BUG <a href="https://github-redirect.dependabot.com/rust-lang/regex/issues/698">#698</a>](<a href="https://github-redirect.dependabot.com/rust-lang/regex/issues/698">rust-lang/regex#698</a>):
Clarify docs for <code>s</code> flag when using a <code>bytes::Regex</code>.</li>
<li>[BUG <a href="https://github-redirect.dependabot.com/rust-lang/regex/issues/711">#711</a>](<a href="https://github-redirect.dependabot.com/rust-lang/regex/issues/711">rust-lang/regex#711</a>):
Clarify <code>is_match</code> docs to indicate that it can match anywhere in string.</li>
</ul>
</blockquote>
</details>
<details>
<summary>Commits</summary>
<ul>
<li><a href="3bcae3b695"><code>3bcae3b</code></a> 1.4.2</li>
<li><a href="d65845181d"><code>d658451</code></a> changelog: 1.4.2</li>
<li><a href="8cb337a0a1"><code>8cb337a</code></a> deps: bump regex-syntax to 0.6.21</li>
<li><a href="d03ae186b5"><code>d03ae18</code></a> regex-syntax-0.6.21</li>
<li><a href="6fdb6e123c"><code>6fdb6e1</code></a> syntax: forbid \P{any}</li>
<li><a href="a7ef5f452e"><code>a7ef5f4</code></a> fuzz: fix release profile</li>
<li><a href="44abc5f7c6"><code>44abc5f</code></a> fuzz: enable optimizations in other profiles</li>
<li><a href="9067dfd7e1"><code>9067dfd</code></a> fuzz: compile fuzzer in release mode</li>
<li><a href="d5bf98f293"><code>d5bf98f</code></a> 1.4.1</li>
<li><a href="1aa1e476de"><code>1aa1e47</code></a> deps: bump regex-syntax minimum version to 0.6.20</li>
<li>Additional commits viewable in <a href="https://github.com/rust-lang/regex/compare/1.3.9...1.4.2">compare view</a></li>
</ul>
</details>
<br />

[![Dependabot compatibility score](https://api.dependabot.com/badges/compatibility_score?dependency-name=regex&package-manager=cargo&previous-version=1.3.9&new-version=1.4.2)](https://dependabot.com/compatibility-score/?dependency-name=regex&package-manager=cargo&previous-version=1.3.9&new-version=1.4.2)

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Cargo.lock

@@ -4752,9 +4752,9 @@ checksum = "4e1b7878800220a76a08f32c057829511440f65528b63b940f2f2bc145d7ac68"
 
 [[package]]
 name = "regex"
-version = "1.3.9"
+version = "1.4.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "9c3780fcf44b193bc4d09f36d2a3c87b251da4a046c87795a0d35f4f927ad8e6"
+checksum = "38cf2c13ed4745de91a5eb834e11c00bcc3709e773173b2ce4c56c9fbde04b9c"
 dependencies = [
  "aho-corasick",
  "memchr",
@@ -4764,9 +4764,9 @@ dependencies = [
 
 [[package]]
 name = "regex-syntax"
-version = "0.6.18"
+version = "0.6.21"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "26412eb97c6b088a6997e05f69403a802a92d520de2f8e63c2b65f9e0f47c4e8"
+checksum = "3b181ba2dcf07aaccad5448e8ead58db5b742cf85dfe035e2227f137a539a189"
 
 [[package]]
 name = "remove_dir_all"