build(deps): bump DavidAnson/markdownlint-cli2-action from 20.0.0 to 21.0.0 (#2183)

Bumps
[DavidAnson/markdownlint-cli2-action](https://github.com/davidanson/markdownlint-cli2-action)
from 20.0.0 to 21.0.0.
<details>
<summary>Commits</summary>
<ul>
<li><a
href="https://github.com/DavidAnson/markdownlint-cli2-action/commit/30a0e04f1870d58f8d717450cc6134995f993c63"><code>30a0e04</code></a>
Update to version 21.0.0.</li>
<li><a
href="https://github.com/DavidAnson/markdownlint-cli2-action/commit/6d4a055237f335b06e764242f92b0e062e7f962d"><code>6d4a055</code></a>
Freshen generated index.js file.</li>
<li><a
href="https://github.com/DavidAnson/markdownlint-cli2-action/commit/d9bf3fbe881bee5546336aecf1561f44a68b7c9f"><code>d9bf3fb</code></a>
Bump markdownlint-cli2 from 0.18.1 to 0.19.0</li>
<li><a
href="https://github.com/DavidAnson/markdownlint-cli2-action/commit/29b4789128417bf7fb32869380e9f0a08c651f13"><code>29b4789</code></a>
Bump <code>@​eslint/js</code> from 9.39.0 to 9.39.1</li>
<li><a
href="https://github.com/DavidAnson/markdownlint-cli2-action/commit/6d600f113b4028d3f120127c298e7597378f2e0a"><code>6d600f1</code></a>
Bump eslint from 9.39.0 to 9.39.1</li>
<li><a
href="https://github.com/DavidAnson/markdownlint-cli2-action/commit/15b21a00afd06ccde3744388f16cbd483012b12d"><code>15b21a0</code></a>
Bump <code>@​eslint/js</code> from 9.38.0 to 9.39.0</li>
<li><a
href="https://github.com/DavidAnson/markdownlint-cli2-action/commit/b259d54d28dff7c01582c0f8fc57b7c3c98ac831"><code>b259d54</code></a>
Bump eslint from 9.38.0 to 9.39.0</li>
<li><a
href="https://github.com/DavidAnson/markdownlint-cli2-action/commit/451cad2cde7304d9c243aaaf2e894d74b428c4be"><code>451cad2</code></a>
Bump eslint-plugin-unicorn from 61.0.2 to 62.0.0</li>
<li><a
href="https://github.com/DavidAnson/markdownlint-cli2-action/commit/c076bbe50e2ba547b66eb496a32a9ea20950d138"><code>c076bbe</code></a>
Bump <code>@​stylistic/eslint-plugin</code> from 5.4.0 to 5.5.0</li>
<li><a
href="https://github.com/DavidAnson/markdownlint-cli2-action/commit/ef464f44a295de1b4c0e9d7337cf31667890dc28"><code>ef464f4</code></a>
Bump <code>@​eslint/js</code> from 9.37.0 to 9.38.0</li>
<li>Additional commits viewable in <a
href="https://github.com/davidanson/markdownlint-cli2-action/compare/992badcdf24e3b8eb7e87ff9287fe931bcb00c6e...30a0e04f1870d58f8d717450cc6134995f993c63">compare
view</a></li>
</ul>
</details>
<br />


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</details>

Author: dscho

.github/workflows/lint-docs.yml

@@ -20,7 +20,7 @@ jobs:
     steps:
       - uses: actions/checkout@v5
 
-      - uses: DavidAnson/markdownlint-cli2-action@992badcdf24e3b8eb7e87ff9287fe931bcb00c6e
+      - uses: DavidAnson/markdownlint-cli2-action@30a0e04f1870d58f8d717450cc6134995f993c63
         with:
           globs: |
             "**/*.md"