fix(deps): update dependency next to v15.1.6

Author: renovate[bot]

pnpm-lock.yaml

@@ -20,7 +20,7 @@
     "clsx": "^2.0.0",
     "graphql": "^16.9.0",
     "lodash.uniqwith": "^4.5.0",
-    "next": "15.1.3",
+    "next": "15.1.6",
     "next-sitemap": "4.2.3",
     "react": "^18.3.1",
     "react-dom": "^18.3.1"