chore: bump next from 12.1.6 to 13.4.12 in /offlinedocs (#8669)

Bumps [next](https://github.com/vercel/next.js) from 12.1.6 to 13.4.12.
- [Release notes](https://github.com/vercel/next.js/releases)
- [Changelog](https://github.com/vercel/next.js/blob/canary/release.js)
- [Commits](https://github.com/vercel/next.js/compare/v12.1.6...v13.4.12)

---
updated-dependencies:
- dependency-name: next
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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

offlinedocs/package.json

@@ -23,7 +23,7 @@
     "front-matter": "4.0.2",
     "fs-extra": "10.1.0",
     "lodash": "4.17.21",
-    "next": "12.1.6",
+    "next": "13.4.12",
     "react": "18.2.0",
     "react-dom": "18.2.0",
     "react-icons": "4.10.1",