Authorizing Loki rules RBAC permissions for Custom logging alerts is unclear

When attempting to follow Authorizing Loki rules RBAC permissions it's not clear what Role Based Access Control (RBAC) rules should be created and assigned to the respective users.

Create a cluster role that defines the necessary RBAC permissions. is a useless statement as it does not specify what kind of permissions should be added to the ClusterRole.

So the documentation needs to be improved to better understand what kind of permissions should be granted, why they should be granted and what the effect is going to be. Hence working with a short example is recommended as otherwise it's not clear what to-do and what will we are trying to achieve.