fix: package.json & yarn.lock to reduce vulnerabilities

The following vulnerabilities are fixed with an upgrade:
- https://snyk.io/vuln/SNYK-JS-NEXT-10259370

Author: snyk-bot

package.json

@@ -36,7 +36,7 @@
     "focus-visible": "^5.2.0",
     "fuse.js": "^6.6.2",
     "js-yaml": "^4.1.0",
-    "next": "~13.1.6",
+    "next": "~15.2.2",
     "next-query-params": "^4.3.0",
     "next-sitemap": "^3.1.17",
     "query-string": "^8.2.0",