add configuration for test gtag container for this pr preview

src/analytics-module.js

@@ -20,6 +20,18 @@ module.exports = () => ({
             name: 'facebook-domain-verification',
             content: 'll8iy5eqaqpremxnd6bo2qg2qjxrtj',
           },
+        },
+        {
+          tagName: 'script',
+          innerHTML: `
+            <!-- Google Tag Manager -->
+            <script>(function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':
+            new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],
+            j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src=
+            'https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);
+            })(window,document,'script','dataLayer','GTM-N6H4MQRW');</script>
+            <!-- End Google Tag Manager -->
+          `
         }
       ],
       preBodyTags: [
@@ -38,8 +50,15 @@ module.exports = () => ({
             <iframe src="https://www.googletagmanager.com/ns.html?id=GTM-55LZM97"
             height="0" width="0" style="display:none;visibility:hidden"></iframe>
           `
+        },
+        {
+          tagName: 'noscript',
+          innerHTML: `
+            <iframe src="https://www.googletagmanager.com/ns.html?id=GTM-N6H4MQRW"
+            height="0" width="0" style="display:none;visibility:hidden"></iframe>
+          `
         }
       ],
     };
   },
-});
+});