Bump next from 14.2.10 to 14.2.21 in /start/src/main/frontend

Bumps [next](https://github.com/vercel/next.js) from 14.2.10 to 14.2.21.
- [Release notes](https://github.com/vercel/next.js/releases)
- [Changelog](https://github.com/vercel/next.js/blob/canary/release.js)
- [Commits](vercel/next.js@v14.2.10...v14.2.21)

---
updated-dependencies:
- dependency-name: next
  dependency-type: direct:production
...

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

Author: dependabot[bot]

start/src/main/frontend/package.json

@@ -12,7 +12,7 @@
   "dependencies": {
     "@tanstack/react-table": "^8.17.3",
     "axios": "^1.7.4",
-    "next": "14.2.10",
+    "next": "14.2.21",
     "react": "^18",
     "react-dom": "^18"
   },