fix(deps): update dependency @next/mdx to v15.5.12 (#576)

Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

Author: renovate[bot]

package.json

@@ -14,7 +14,7 @@
     "e2e": "playwright test"
   },
   "dependencies": {
-    "@next/mdx": "15.5.11",
+    "@next/mdx": "15.5.12",
     "motion": "^10.18.0",
     "next": "16.1.6",
     "normalize.css": "8.0.1",