Restrict labels in Loki in OCP 4

Issue

• A normal user is able to see the labels from resources (namespaces, pods) where has no access when accessing an external tool connected to Loki
• A normal user should be only able to see the labels for the resources from OpenShift that has access when accessing the logs stored in Loki from an external tool connected to Loki
• Needed to restrict the labels that a user can see from an external tool connected to LokiStack