Simplify URL and enable in production only

Author: djhi

packages/ra-core/src/core/CoreAdminUI.tsx

@@ -57,11 +57,11 @@ const CoreAdminUI: FunctionComponent<AdminUIProps> = ({
 }) => {
     return (
         <>
-            {process.env.NODE_ENV === 'development' &&
+            {process.env.NODE_ENV === 'production' &&
             disableTelemetry !== true &&
             typeof window !== 'undefined' ? (
                 <img
-                    src={`https://react-admin-telemetry.marmelab.com/react-admin-telemetry?domain=${window.location.hostname}`}
+                    src="https://react-admin-telemetry.marmelab.com/react-admin-telemetry"
                     width="0"
                     height=""
                     alt=""