fix: apps/auth-test/package.json to reduce vulnerabilities

The following vulnerabilities are fixed with an upgrade:
- https://snyk.io/vuln/SNYK-JS-NEXT-14173355

Author: snyk-bot

apps/auth-test/package.json

@@ -10,7 +10,7 @@
     "setup": "tsx scripts/ternsecure-sw.ts"
   },
   "dependencies": {
-    "next": "15.3.2",
+    "next": "15.3.6",
     "react": "^19.0.0",
     "react-dom": "^19.0.0"
   },