changed to jekyll env check in conditional

Author: bsanchez-the-roach

src/current/_includes/google_tag_manager.html

@@ -1,15 +1,13 @@
+{% if jekyll.environment == 'production' %}
 <!-- Google Tag Manager -->
-<script>
-if (window.location.hostname == 'cockroachlabs.com') {
-  (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':
+<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-NR8LC4');
-}
-</script>
-<!-- End Google Tag Manager -->
+    })(window,document,'script','dataLayer','GTM-NR8LC4');</script>
+    <!-- End Google Tag Manager -->
 <!-- Google Tag Manager (noscript) -->
 <noscript><iframe src="https://www.googletagmanager.com/ns.html?id=GTM-NR8LC4"
     height="0" width="0" style="display:none;visibility:hidden"></iframe></noscript>
-    <!-- End Google Tag Manager (noscript) -->
+    <!-- End Google Tag Manager (noscript) -->
+{% endif %}