chore(deps): bump zod and next in /who-metrics-ui

Removes [zod](https://github.com/colinhacks/zod). It's no longer used after updating ancestor dependency [next](https://github.com/vercel/next.js). These dependencies need to be updated together.


Removes `zod`

Updates `next` from 13.5.1 to 13.5.6
- [Release notes](https://github.com/vercel/next.js/releases)
- [Changelog](https://github.com/vercel/next.js/blob/canary/release.js)
- [Commits](vercel/next.js@v13.5.1...v13.5.6)

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

Signed-off-by: dependabot[bot] <support@github.com>

who-metrics-ui/package.json

@@ -27,7 +27,7 @@
     "json-2-csv": "^5.0.1",
     "kysely": "^0.23.4",
     "kysely-planetscale": "^1.3.0",
-    "next": "^13.5.1",
+    "next": "^13.5.6",
     "next-auth": "^4.24.5",
     "next-themes": "^0.2.1",
     "postcss": "^8.4.31",