Tag manager needs additional CSP adjustments. (#456)

index.html

@@ -16,8 +16,8 @@
       http-equiv="Content-Security-Policy" 
       content="
         default-src 'none'; 
-        style-src 'self' 'unsafe-inline' https://use.typekit.net https://p.typekit.net;
-        script-src 'self' https://www.googletagmanager.com/gtm.js 'unsafe-eval'; 
+        style-src 'self' 'unsafe-inline' https://use.typekit.net https://p.typekit.net https://tagmanager.google.com/ https://www.googletagmanager.com/;
+        script-src 'self' https://tagmanager.google.com/ https://www.googletagmanager.com/ 'unsafe-eval' 'unsafe-inline';         
         connect-src 'self' localhost:* https://allsearch-api.princeton.edu https://allsearch-api-staging.princeton.edu https://bibdata.princeton.edu https://bibdata-staging.lib.princeton.edu https://api.honeybadger.io https://www.google-analytics.com; 
         font-src 'self' https://use.typekit.net; 
         base-uri 'none';