Bump serde_yaml from 0.9.4 to 0.9.9 (#2236)

Bumps [serde_yaml](https://github.com/dtolnay/serde-yaml) from 0.9.4 to 0.9.9.
<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>0.9.9</h2>
<ul>
<li>Add <a href="https://docs.rs/serde_yaml/0.9.9/serde_yaml/with/singleton_map_recursive/index.html">serde_yaml::with::singleton_map_recursive</a></li>
</ul>
<h2>0.9.8</h2>
<ul>
<li>Fix serialization of <code>TaggedValue</code> when used with <code>to_value</code> (<a href="https://github-redirect.dependabot.com/dtolnay/serde-yaml/issues/313">#313</a>)</li>
</ul>
<h2>0.9.7</h2>
<ul>
<li>Allow an empty plain scalar to deserialize as an empty map or seq (<a href="https://github-redirect.dependabot.com/dtolnay/serde-yaml/issues/304">#304</a>)</li>
</ul>
<h2>0.9.6</h2>
<ul>
<li>Fix tag not getting serialized in certain map values (<a href="https://github-redirect.dependabot.com/dtolnay/serde-yaml/issues/302">#302</a>)</li>
</ul>
<h2>0.9.5</h2>
<ul>
<li>Implement <code>Display</code> trait for <code>serde_yaml::value::Tag</code> (<a href="https://github-redirect.dependabot.com/dtolnay/serde-yaml/issues/307">#307</a>, thanks <a href="https://github.com/masinc"><code>@​masinc</code></a>)</li>
</ul>
</blockquote>
</details>
<details>
<summary>Commits</summary>
<ul>
<li><a href="3ef5ebb1c9"><code>3ef5ebb</code></a> Release 0.9.9</li>
<li><a href="366dadc4d2"><code>366dadc</code></a> Merge pull request <a href="https://github-redirect.dependabot.com/dtolnay/serde-yaml/issues/315">#315</a> from dtolnay/recursive</li>
<li><a href="7d4528a7e3"><code>7d4528a</code></a> Add serde_yaml::with::singleton_map_recursive</li>
<li><a href="d792a6595a"><code>d792a65</code></a> Release 0.9.8</li>
<li><a href="c3b792e79d"><code>c3b792e</code></a> Propagate collect_str in singleton_map Serializer</li>
<li><a href="ef6f2c5494"><code>ef6f2c5</code></a> Merge pull request <a href="https://github-redirect.dependabot.com/dtolnay/serde-yaml/issues/314">#314</a> from dtolnay/tagged</li>
<li><a href="e66524192b"><code>e665241</code></a> Fix serialization of TaggedValue in to_value</li>
<li><a href="d61a5714d1"><code>d61a571</code></a> Add TaggedValue to_value/from_value test</li>
<li><a href="144eb66782"><code>144eb66</code></a> Ignore too_many_lines pedantic clippy lint</li>
<li><a href="a16e1ada4b"><code>a16e1ad</code></a> Put value serializer data structures next to impls</li>
<li>Additional commits viewable in <a href="https://github.com/dtolnay/serde-yaml/compare/0.9.4...0.9.9">compare view</a></li>
</ul>
</details>
<br />


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</details>

Cargo.lock

@@ -1490,9 +1490,9 @@ dependencies = [
 
 [[package]]
 name = "serde_yaml"
-version = "0.9.4"
+version = "0.9.9"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "79b7c9017c64a49806c6e8df8ef99b92446d09c92457f85f91835b01a8064ae0"
+checksum = "f50845f68d5c693aac7d72a25415ddd21cb8182c04eafe447b73af55a05f9e1b"
 dependencies = [
  "indexmap",
  "itoa 1.0.2",

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 = "1.0.143", features = ["derive"] }
-serde_yaml = "0.9.4"
+serde_yaml = "0.9.9"
 serde_json = "1.0.83"
 bitflags = "1.3.2"
 regex = "1.6.0"