Update dependency nuxt-gtag to v4

Author: renovate[bot]

package-lock.json

@@ -21,7 +21,7 @@
     "@nuxtjs/robots": "5.2.10",
     "@nuxtjs/sitemap": "7.2.10",
     "nuxt": "^3.16.2",
-    "nuxt-gtag": "3.0.2",
+    "nuxt-gtag": "4.0.0",
     "nuxt-llms": "0.1.2",
     "nuxt-og-image": "^5.1.1"
   },