add google tracking js

gatsby-config.js

@@ -11,6 +11,12 @@ module.exports = {
         path: `${__dirname}/src`,
       },
     },
+    {
+      resolve: 'gatsby-plugin-google-analytics',
+      options: {
+        trackingId: "G-TVTHN7455T",
+      },
+    },
     "gatsby-plugin-image",
     "gatsby-plugin-sharp",
     "gatsby-transformer-sharp",