feat: remove plugin

Author: hondahmd

package.json

@@ -16,7 +16,6 @@
   },
   "dependencies": {
     "@docusaurus/core": "^3.5.2",
-    "@docusaurus/plugin-google-gtag": "^3.6.2",
     "@docusaurus/preset-classic": "^3.5.2",
     "@lottielab/lottie-player": "^1.1.2",
     "@mdx-js/react": "^3.0.0",