Deps: Update dependency autoprefixer to v10.4.21.

Author: renovate[bot]

package.json

@@ -66,7 +66,7 @@
         "@types/react": "18.3.12",
         "@typescript-eslint/eslint-plugin": "8.13.0",
         "@typescript-eslint/parser": "8.13.0",
-        "autoprefixer": "10.4.20",
+        "autoprefixer": "10.4.21",
         "concurrently": "9.1.0",
         "eslint": "8.57.1",
         "eslint-config-next": "14.2.17",