fix: examples/auth/nextjs/package.json & examples/auth/nextjs/package-lock.json to reduce vulnerabilities

The following vulnerabilities are fixed with an upgrade:
- https://snyk.io/vuln/SNYK-JS-NEXT-14400636
- https://snyk.io/vuln/SNYK-JS-NANOID-8492085

Author: snyk-bot

examples/auth/nextjs/package-lock.json

@@ -10,7 +10,7 @@
     "@supabase/supabase-js": "latest",
     "autoprefixer": "10.4.17",
     "geist": "^1.2.1",
-    "next": "latest",
+    "next": "14.2.35",
     "postcss": "8.4.33",
     "react": "18.2.0",
     "react-dom": "18.2.0",