fix: 🚀 npm for astro-docs: bump @astrojs/mdx in /docs (#207)

Bumps [@astrojs/mdx](https://github.com/withastro/astro/tree/HEAD/packages/integrations/mdx) from 0.17.2 to 0.19.0.
- [Release notes](https://github.com/withastro/astro/releases)
- [Changelog](https://github.com/withastro/astro/blob/main/packages/integrations/mdx/CHANGELOG.md)
- [Commits](https://github.com/withastro/astro/commits/@astrojs/[email protected]/packages/integrations/mdx)

---
updated-dependencies:
- dependency-name: "@astrojs/mdx"
  dependency-type: direct:development
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <[email protected]>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

docs/package.json

@@ -29,7 +29,7 @@
     "typescript": "^5.0.4"
   },
   "devDependencies": {
-    "@astrojs/mdx": "^0.17.2",
+    "@astrojs/mdx": "^0.19.0",
     "@astrojs/sitemap": "^1.2.2",
     "astro-robots-txt": "^0.4.1",
     "html-escaper": "^3.0.3",