chore(deps-dev): Update mkdocs-material requirement from ~=8.3.8 to ~=8.3.9 in /gh-pages (#3654)

Updates the requirements on [mkdocs-material](https://github.com/squidfunk/mkdocs-material) to permit the latest version.
<details>
<summary>Release notes</summary>
<p><em>Sourced from <a href="https://github.com/squidfunk/mkdocs-material/releases">mkdocs-material's releases</a>.</em></p>
<blockquote>
<h2>mkdocs-material-8.3.9</h2>
<ul>
<li>Updated Taiwanese translations for search</li>
<li>Allow ids for content tabs with special characters (for mkdocstrings)</li>
<li>Fixed <a href="https://github-redirect.dependabot.com/squidfunk/mkdocs-material/issues/4083">#4083</a>: home not clickable when using versioning (8.3.5 regression)</li>
</ul>
</blockquote>
</details>
<details>
<summary>Changelog</summary>
<p><em>Sourced from <a href="https://github.com/squidfunk/mkdocs-material/blob/master/CHANGELOG">mkdocs-material's changelog</a>.</em></p>
<blockquote>
<p>mkdocs-material-8.3.9+insiders-4.20.1 (2022-07-11)</p>
<ul>
<li>Fixed <a href="https://github-redirect.dependabot.com/squidfunk/mkdocs-material/issues/4105">#4105</a>: Tags plugin fails if tags_file is not set (4.20.0 regression)</li>
</ul>
<p>mkdocs-material-8.3.9+insiders-4.20.0 (2022-07-07)</p>
<ul>
<li>Added support for additional tags indexes</li>
<li>Fixed <a href="https://github-redirect.dependabot.com/squidfunk/mkdocs-material/issues/4100">#4100</a>: Tag icons not shown in tags index</li>
</ul>
<p>mkdocs-material-8.3.9+insiders-4.19.2 (2022-07-04)</p>
<ul>
<li>Fixed <a href="https://github-redirect.dependabot.com/squidfunk/mkdocs-material/issues/4051">#4051</a>: Privacy plugin fails if symlinking isn't allowed on Windows</li>
</ul>
<p>mkdocs-material-8.3.9 (2022-07-04)</p>
<ul>
<li>Updated Taiwanese translations for search</li>
<li>Allow ids for content tabs with special characters (for mkdocstrings)</li>
<li>Fixed <a href="https://github-redirect.dependabot.com/squidfunk/mkdocs-material/issues/4083">#4083</a>: home not clickable when using versioning (8.3.5 regression)</li>
</ul>
<p>mkdocs-material-8.3.8+insiders-4.19.1 (2022-06-25)</p>
<ul>
<li>Added mkdocs-git-committers-plugin to Dockerfile</li>
<li>Added mkdocs-git-revision-date-localized-plugin to Dockerfile</li>
</ul>
<p>mkdocs-material-8.3.8+insiders-4.19.0 (2022-06-24)</p>
<ul>
<li>Added support for document contributors</li>
<li>Updated French translations for cookie consent</li>
</ul>
<p>mkdocs-material-8.3.8 (2022-06-24)</p>
<ul>
<li>Fixed <a href="https://github-redirect.dependabot.com/squidfunk/mkdocs-material/issues/4053">#4053</a>: Limit width of videos to content area</li>
<li>Fixed empty tags in front matter breaking search</li>
</ul>
<p>mkdocs-material-8.3.7 (2022-06-22)</p>
<ul>
<li>Fixed search being stuck initializing when using tags (8.3.4 regression)</li>
</ul>
<p>mkdocs-material-8.3.6+insiders-4.18.2 (2022-06-16)</p>
<ul>
<li>Fixed <a href="https://github-redirect.dependabot.com/squidfunk/mkdocs-material/issues/4026">#4026</a>: Fixed tooltips not mounted for nested navigation links</li>
</ul>
<p>mkdocs-material-8.3.6 (2022-06-16)</p>
<ul>
<li>Fixed <a href="https://github-redirect.dependabot.com/squidfunk/mkdocs-material/issues/4028">#4028</a>: Links not clickable when using versioning (8.3.5 regression)</li>
</ul>
<p>mkdocs-material-8.3.5+insiders-4.18.1 (2022-06-14)</p>
<ul>
<li>Fixed <a href="https://github-redirect.dependabot.com/squidfunk/mkdocs-material/issues/3990">#3990</a>: Chinese search highlighting not working on non-boundaries</li>
</ul>

</blockquote>
<p>... (truncated)</p>
</details>
<details>
<summary>Commits</summary>
<ul>
<li><a href="https://github.com/squidfunk/mkdocs-material/commit/87cac53bc6163ed59ded15cf496a5f608a885e07"><code>87cac53</code></a> Prepare 8.3.9 release</li>
<li><a href="https://github.com/squidfunk/mkdocs-material/commit/409e342dfa5dc9afbe39200ea4245c90bf6dec4d"><code>409e342</code></a> Updated dependencies</li>
<li><a href="https://github.com/squidfunk/mkdocs-material/commit/a261130204371e7dab3d4a961926b2cde43048b4"><code>a261130</code></a> Fixed home button not working occasionally when using versioning</li>
<li><a href="https://github.com/squidfunk/mkdocs-material/commit/adabdd0bec756203653d8230a89fdf9187afe07f"><code>adabdd0</code></a> Allow pymdownx.magiclink without arguments in schema</li>
<li><a href="https://github.com/squidfunk/mkdocs-material/commit/4151f326dcfc2734eed62bc4f02b8ee415f3a429"><code>4151f32</code></a> Merge branch 'master' of github.com:squidfunk/mkdocs-material</li>
<li><a href="https://github.com/squidfunk/mkdocs-material/commit/209856e724e67aac689744223f48f13e1c2fe3c4"><code>209856e</code></a> Allow ids for content tabs with special characters</li>
<li><a href="https://github.com/squidfunk/mkdocs-material/commit/016300d0504ff7d9560092492a10546e3dc21f7e"><code>016300d</code></a> Documentation (<a href="https://github-redirect.dependabot.com/squidfunk/mkdocs-material/issues/4080">#4080</a>)</li>
<li><a href="https://github.com/squidfunk/mkdocs-material/commit/940cfb27f18420316791920c8a421cb7781269f4"><code>940cfb2</code></a> Added Elastic to premium sponsors</li>
<li><a href="https://github.com/squidfunk/mkdocs-material/commit/415daf62f5429c723e4ce33c6e9ad791b122dcc8"><code>415daf6</code></a> Updated documentation workflow</li>
<li><a href="https://github.com/squidfunk/mkdocs-material/commit/40fe9f6ffdfb46fe4e2b7cb857d1c06c0d812e62"><code>40fe9f6</code></a> Updated dependencies</li>
<li>Additional commits viewable in <a href="https://github.com/squidfunk/mkdocs-material/compare/8.3.8...8.3.9">compare view</a></li>
</ul>
</details>
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Author: dependabot[bot]

gh-pages/requirements-dev.txt

@@ -1,4 +1,4 @@
 mkdocs~=1.3.0
 mkdocs-awesome-pages-plugin~=2.7.0
-mkdocs-material~=8.3.8
+mkdocs-material~=8.3.9
 mkdocs-git-revision-date-plugin~=0.3.2