Bump next from 14.2.15 to 14.2.21 in /front (#98)

Bumps [next](https://github.com/vercel/next.js) from 14.2.15 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@v14.2.15...v14.2.21)

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

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Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

front/package-lock.json

@@ -11,7 +11,7 @@
   },
   "dependencies": {
     "autoprefixer": "^10.4.0",
-    "next": "^14.2.15",
+    "next": "^14.2.21",
     "papaparse": "^5.3.1",
     "postcss": "^8.4.31",
     "react": "^17.0.2",