Bump @astrojs/mdx from 4.3.0 to 4.3.12 (#2)

Bumps [@astrojs/mdx](https://github.com/withastro/astro/tree/HEAD/packages/integrations/mdx) from 4.3.0 to 4.3.12.
- [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/mdx@4.3.12/packages/integrations/mdx)

---
updated-dependencies:
- dependency-name: "@astrojs/mdx"
  dependency-version: 4.3.12
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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Author: dependabot[bot]

package.json

@@ -21,7 +21,7 @@
   },
   "dependencies": {
     "@astrojs/check": "^0.9.4",
-    "@astrojs/mdx": "^4.3.0",
+    "@astrojs/mdx": "^4.3.12",
     "@astrojs/rss": "^4.0.12",
     "@astrojs/sitemap": "^3.4.1",
     "@github/clipboard-copy-element": "^1.3.0",