chore(deps): bump next from 14.2.26 to 15.2.4 in /docs

Bumps [next](https://github.com/vercel/next.js) from 14.2.26 to 15.2.4.
- [Release notes](https://github.com/vercel/next.js/releases)
- [Changelog](https://github.com/vercel/next.js/blob/canary/release.js)
- [Commits](vercel/next.js@v14.2.26...v15.2.4)

---
updated-dependencies:
- dependency-name: next
  dependency-version: 15.2.4
  dependency-type: direct:production
...

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

Author: dependabot[bot]

docs/package.json

@@ -21,7 +21,7 @@
     "classnames": "^2.3.2",
     "cubedev-tracking": "^1.1.0",
     "date-fns": "^2.30.0",
-    "next": "^14.2.26",
+    "next": "^15.2.4",
     "next-sitemap": "^4.1.3",
     "nextra": "^2.13.2",
     "nextra-theme-docs": "^2.4.0",