chore(deps-dev): Update mkdocs-material requirement from ~=9.1.6 to ~…

…=9.1.8 in /gh-pages (#4075)

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-9.1.8</h2>
<ul>
<li>Fixed <a href="https://redirect.github.com/squidfunk/mkdocs-material/issues/5417">#5417</a>: Theme breaks when <code>palette</code> is not defined (9.1.7 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-9.1.8 (2023-04-24)</p>
<ul>
<li>Fixed <a href="https://redirect.github.com/squidfunk/mkdocs-material/issues/5417">#5417</a>: Theme breaks when palette is not defined (9.1.7 regression)</li>
</ul>
<p>mkdocs-material-9.1.7+insiders-4.32.6 (2023-04-22)</p>
<ul>
<li>Fixed <a href="https://redirect.github.com/squidfunk/mkdocs-material/issues/5336">#5336</a>: Interplay of blog plugin with git-revision-date-localized</li>
</ul>
<p>mkdocs-material-9.1.7 (2023-04-22)</p>
<ul>
<li>Updated Persian (Farsi) and Turkish translations</li>
<li>Fixed <a href="https://redirect.github.com/squidfunk/mkdocs-material/issues/5401">#5401</a>: Added missing flag to disable built-in tags plugin</li>
<li>Fixed <a href="https://redirect.github.com/squidfunk/mkdocs-material/issues/5206">#5206</a>: Ensure defaults are set for primary and accent colors</li>
<li>Fixed unnecessary inclusion of palette CSS when unused</li>
</ul>
<p>mkdocs-material-9.1.6+insiders-4.32.5 (2023-04-07)</p>
<ul>
<li>Fixed <a href="https://redirect.github.com/squidfunk/mkdocs-material/issues/5322">#5322</a>: Navigation tabs hoist nested page icons</li>
</ul>
<p>mkdocs-material-9.1.6 (2023-04-07)</p>
<ul>
<li>Updated Persian (Farsi) translations</li>
<li>Fixed <a href="https://redirect.github.com/squidfunk/mkdocs-material/issues/5300">#5300</a>: Boxes in Mermaid sequence diagrams not color-abiding</li>
</ul>
<p>mkdocs-material-9.1.5 (2023-03-31)</p>
<ul>
<li>Updated Lithuanian and Japanese translations</li>
<li>Updated Mermaid.js to version 9.4.3</li>
<li>Fixed <a href="https://redirect.github.com/squidfunk/mkdocs-material/issues/5290">#5290</a>: Footer previous/next labels cut-off for short page titles</li>
</ul>
<p>mkdocs-material-9.1.4+insiders-4.32.4 (2023-03-24)</p>
<ul>
<li>Fixed <a href="https://redirect.github.com/squidfunk/mkdocs-material/issues/5241">#5241</a>: Built-in typeset plugin jams navigation for anchors in headings</li>
</ul>
<p>mkdocs-material-9.1.4 (2023-03-24)</p>
<ul>
<li>Fixed <a href="https://redirect.github.com/squidfunk/mkdocs-material/issues/5239">#5239</a>: Instant loading breaks anchors in details (9.1.1 regression)</li>
<li>Fixed <a href="https://redirect.github.com/squidfunk/mkdocs-material/issues/5211">#5211</a>: Anchor following not working for Chinese (9.1.2 regression)</li>
</ul>
<p>mkdocs-material-9.1.3 (2023-03-14)</p>
<ul>
<li>Added Kurdish (Soranî) translations</li>
<li>Updated Norwegian (Bokmål), Portuguese and Romanian translations</li>
<li>Improved compatibility with mkdocs-jupyter plugin</li>
<li>Fixed <a href="https://redirect.github.com/squidfunk/mkdocs-material/issues/5198">#5198</a>: Built-in search plugin not filtering script and style tags</li>
<li>Fixed <a href="https://redirect.github.com/squidfunk/mkdocs-material/issues/5176">#5176</a>: Back-to-top + instant loading not working (9.1.1 regression)</li>
</ul>
<p>mkdocs-material-9.1.2+insiders-4.32.3 (2023-03-09)</p>
<ul>
<li>Fixed Docker image release workflow (9.1.0 regression)</li>
</ul>

</blockquote>
<p>... (truncated)</p>
</details>
<details>
<summary>Commits</summary>
<ul>
<li><a href="https://github.com/squidfunk/mkdocs-material/commit/2ac2cbc3ae2358767d1311797f9a185540f83271"><code>2ac2cbc</code></a> Prepare 9.1.8 release</li>
<li><a href="https://github.com/squidfunk/mkdocs-material/commit/f0d506c4461d5f3ed41b65ffe051dd2b018dac0d"><code>f0d506c</code></a> Fixed theme breaking when no palette is defined</li>
<li><a href="https://github.com/squidfunk/mkdocs-material/commit/0028518f1a062a66d0b42ad5b74093cca936b3b7"><code>0028518</code></a> Prepare 9.1.7 release</li>
<li><a href="https://github.com/squidfunk/mkdocs-material/commit/6398f529d60e4c0e3b1b97a2b62ba1fd56c4bcc3"><code>6398f52</code></a> Merge branch 'master' of github.com:squidfunk/mkdocs-material</li>
<li><a href="https://github.com/squidfunk/mkdocs-material/commit/6f13021a3824a63c7b7b9f0136c945753f10d738"><code>6f13021</code></a> Fixed unnecessary inclusion of palette.css</li>
<li><a href="https://github.com/squidfunk/mkdocs-material/commit/6fe1d556071416122af362064c78873babcfe9cf"><code>6fe1d55</code></a> Always set default primary and accent colors</li>
<li><a href="https://github.com/squidfunk/mkdocs-material/commit/207fd4029f3870c73b9a86c78bb89aaca8b83cf9"><code>207fd40</code></a> Merge pull request <a href="https://redirect.github.com/squidfunk/mkdocs-material/issues/5389">#5389</a> from robingenz/patch-1</li>
<li><a href="https://github.com/squidfunk/mkdocs-material/commit/ba90cb1ccda74118bcf694c28e32fb1570ec8ea1"><code>ba90cb1</code></a> Added missing enabled setting for tags plugin</li>
<li><a href="https://github.com/squidfunk/mkdocs-material/commit/c0cdb3ca1f7ce1cf85d021f39733c8ea14244c9a"><code>c0cdb3c</code></a> Updated Turkish translations</li>
<li><a href="https://github.com/squidfunk/mkdocs-material/commit/ab94f5f648d8b781461c77a901458e142d8d4277"><code>ab94f5f</code></a> Updated Persian (Farsi) translations</li>
<li>Additional commits viewable in <a href="https://github.com/squidfunk/mkdocs-material/compare/9.1.6...9.1.8">compare view</a></li>
</ul>
</details>
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</details>

gh-pages/requirements-dev.txt

@@ -1,4 +1,4 @@
 mkdocs~=1.4.2
 mkdocs-awesome-pages-plugin~=2.9.0
-mkdocs-material~=9.1.6
+mkdocs-material~=9.1.8
 mkdocs-git-revision-date-plugin~=0.3.2