updated description when using cluster-scoped flag (#1190)

* updated description when using cluster-scoped flag 

When using ` cluster-scoped` flag, in the file `deploy/role_binding.yaml` CluserRole is used instead of Role

* Improved the documentation

Changed from: 
Use `ClusterRole` instead of `Role`  
to 
Use `ClusterRole` instead of `Role` for roleRef

Author: cmendible

doc/user-guide.md

@@ -61,6 +61,7 @@ Using `--cluster-scoped` will scaffold the new operator with the following modif
 * `deploy/role.yaml` - Use `ClusterRole` instead of `Role`
 * `deploy/role_binding.yaml`:
   * Use `ClusterRoleBinding` instead of `RoleBinding`
+  * Use `ClusterRole` instead of `Role` for roleRef
   * Set the subject namespace to `REPLACE_NAMESPACE`. This must be changed to the namespace in which the operator is deployed.
 
 ### Manager