fix(deps): update dependency next to v15.4.8 [security] (#2302)

Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

Author: renovate[bot]

examples/gnt/package.json

@@ -16,7 +16,7 @@
     "gqty": "workspace:^",
     "graphql": "^16.11.0",
     "graphql-ws": "^5.16.2",
-    "next": "15.4.7",
+    "next": "15.4.8",
     "react": "^18.3.1",
     "react-dom": "^18.3.1"
   },