fix: waltid-applications/waltid-web-portal/package.json to reduce vulnerabilities

The following vulnerabilities are fixed with an upgrade:
- https://snyk.io/vuln/SNYK-JS-NEXT-18233136
- https://snyk.io/vuln/SNYK-JS-NEXT-18233752

Author: snyk-bot

waltid-applications/waltid-web-portal/package.json

@@ -22,7 +22,7 @@
     "axios": "^1.7.2",
     "eslint": "9.39.2",
     "eslint-config-next": "14.2.35",
-    "next": "16.2.6",
+    "next": "16.2.11",
     "postcss": "8.5.14",
     "react": "18.3.1",
     "react-dom": "18.3.1",