chore: bump @next/mdx from 11.1.2 to 14.2.13

Bumps [@next/mdx](https://github.com/vercel/next.js/tree/HEAD/packages/next-mdx) from 11.1.2 to 14.2.13.
- [Release notes](https://github.com/vercel/next.js/releases)
- [Changelog](https://github.com/vercel/next.js/blob/canary/release.js)
- [Commits](https://github.com/vercel/next.js/commits/v14.2.13/packages/next-mdx)

---
updated-dependencies:
- dependency-name: "@next/mdx"
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <[email protected]>

packages/website/package.json

@@ -31,7 +31,7 @@
     "@emotion/core": "^10.0.17",
     "@mdx-js/loader": "^2.1.5",
     "@mdx-js/react": "^2.1.1",
-    "@next/mdx": "^11.1.2",
+    "@next/mdx": "^14.2.13",
     "@segment/snippet": "^4.15.3",
     "create-emotion-server": "^10.0.27",
     "date-fns": "^2.28.0",