Bump serde_yaml from 0.9.2 to 0.9.4 (#2214)

Bumps [serde_yaml](https://github.com/dtolnay/serde-yaml) from 0.9.2 to 0.9.4.
<details>
<summary>Release notes</summary>
<p><em>Sourced from <a href="https://github.com/dtolnay/serde-yaml/releases">serde_yaml's releases</a>.</em></p>
<blockquote>
<h2>0.9.4</h2>
<ul>
<li>Add <code>serde_yaml::with::singleton_map</code> for serialization of enums as a 1-entry map (<a href="https://github-redirect.dependabot.com/dtolnay/serde-yaml/issues/300">#300</a>)</li>
<li>Reject duplicate keys when deserializing <code>Mapping</code> or <code>Value</code> (<a href="https://github-redirect.dependabot.com/dtolnay/serde-yaml/issues/301">#301</a>)</li>
</ul>
<h2>0.9.3</h2>
<ul>
<li>Add categories to crates.io metadata</li>
<li>Add keywords to crates.io metadata</li>
</ul>
</blockquote>
</details>
<details>
<summary>Commits</summary>
<ul>
<li><a href="d282c40d09"><code>d282c40</code></a> Release 0.9.4</li>
<li><a href="50f6ecd061"><code>50f6ecd</code></a> Merge pull request <a href="https://github-redirect.dependabot.com/dtolnay/serde-yaml/issues/301">#301</a> from dtolnay/duplicate</li>
<li><a href="ec1c1e42cb"><code>ec1c1e4</code></a> Error on duplicate key when deserializing Mapping</li>
<li><a href="13837fd568"><code>13837fd</code></a> Delegate Value deserialization to Vec's and Mapping's impl</li>
<li><a href="f3504fbd17"><code>f3504fb</code></a> Merge pull request <a href="https://github-redirect.dependabot.com/dtolnay/serde-yaml/issues/300">#300</a> from dtolnay/with</li>
<li><a href="f344c5643c"><code>f344c56</code></a> Add a singleton_map module for serde's 'with' attribute</li>
<li><a href="7e1b160b29"><code>7e1b160</code></a> Pull in fixes from unsafe-libyaml 0.2.2</li>
<li><a href="3dceb159eb"><code>3dceb15</code></a> Add test of serialize_key/serialize_value map</li>
<li><a href="f7b55f1a62"><code>f7b55f1</code></a> Fix serialize_key of 1-entry maps</li>
<li><a href="5299f1e5be"><code>5299f1e</code></a> Derive Debug for emitter's Event</li>
<li>Additional commits viewable in <a href="https://github.com/dtolnay/serde-yaml/compare/0.9.2...0.9.4">compare view</a></li>
</ul>
</details>
<br />


[![Dependabot compatibility score](https://dependabot-badges.githubapp.com/badges/compatibility_score?dependency-name=serde_yaml&package-manager=cargo&previous-version=0.9.2&new-version=0.9.4)](https://docs.github.com/en/github/managing-security-vulnerabilities/about-dependabot-security-updates#about-compatibility-scores)

Dependabot will resolve any conflicts with this PR as long as you don't alter it yourself. You can also trigger a rebase manually by commenting `@dependabot rebase`.

[//]: # (dependabot-automerge-start)
[//]: # (dependabot-automerge-end)

---

<details>
<summary>Dependabot commands and options</summary>
<br />

You can trigger Dependabot actions by commenting on this PR:
- `@dependabot rebase` will rebase this PR
- `@dependabot recreate` will recreate this PR, overwriting any edits that have been made to it
- `@dependabot merge` will merge this PR after your CI passes on it
- `@dependabot squash and merge` will squash and merge this PR after your CI passes on it
- `@dependabot cancel merge` will cancel a previously requested merge and block automerging
- `@dependabot reopen` will reopen this PR if it is closed
- `@dependabot close` will close this PR and stop Dependabot recreating it. You can achieve the same result by closing it manually
- `@dependabot ignore this major version` will close this PR and stop Dependabot creating any more for this major version (unless you reopen the PR or upgrade to it yourself)
- `@dependabot ignore this minor version` will close this PR and stop Dependabot creating any more for this minor version (unless you reopen the PR or upgrade to it yourself)
- `@dependabot ignore this dependency` will close this PR and stop Dependabot creating any more for this dependency (unless you reopen the PR or upgrade to it yourself)


</details>

Cargo.lock

@@ -1450,9 +1450,9 @@ dependencies = [
 
 [[package]]
 name = "serde_yaml"
-version = "0.9.2"
+version = "0.9.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "826f989c0f374733af6c286f4822f293bc738def07e2782dc1cbb899960a504a"
+checksum = "79b7c9017c64a49806c6e8df8ef99b92446d09c92457f85f91835b01a8064ae0"
 dependencies = [
  "indexmap",
  "itoa 1.0.2",
@@ -1706,9 +1706,9 @@ checksum = "957e51f3646910546462e67d5f7599b9e4fb8acdd304b087a6494730f9eebf04"
 
 [[package]]
 name = "unsafe-libyaml"
-version = "0.2.1"
+version = "0.2.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "9dc1c637311091be28e5d462c07db78081e5828da80ba22605c81c4ad6f7f813"
+checksum = "931179334a56395bcf64ba5e0ff56781381c1a5832178280c7d7f91d1679aeb0"
 
 [[package]]
 name = "utf8parse"

boa_tester/Cargo.toml

@@ -17,7 +17,7 @@ boa_interner = { path = "../boa_interner", version = "0.15.0" }
 boa_gc = { path = "../boa_gc", version = "0.15.0" }
 structopt = "0.3.26"
 serde = { version = "1.0.141", features = ["derive"] }
-serde_yaml = "0.9.2"
+serde_yaml = "0.9.4"
 serde_json = "1.0.82"
 bitflags = "1.3.2"
 regex = "1.6.0"