chore(deps): bump next in /packages/sdk/vercel/examples/complete

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]

packages/sdk/vercel/examples/complete/package.json

@@ -14,7 +14,7 @@
     "@vercel/edge-config": "^1.1.0",
     "launchdarkly-js-client-sdk": "^3.1.3",
     "launchdarkly-react-client-sdk": "^3.0.6",
-    "next": "14.2.26",
+    "next": "15.2.4",
     "react": "18.2.0",
     "react-dom": "18.2.0"
   },