docs: adds google analytics tag (#1540)

Author: lukegalbraithrussell

docs/docusaurus.config.js

@@ -43,6 +43,9 @@ const config = {
         theme: {
           customCss: "./src/css/custom.css",
         },
+        gtag: {
+          trackingID: "G-9H1YZW28BG",
+        },
       }),
     ],
   ],