Re-enable exposure of prometheus endpoints for external consumption

1. Proposed title of this feature request
Re-enable exposure of prometheus endpoints for external consumption.

2. What is the nature and description of the request?
As part of thr work in making the OCP environment an abstract for the developer. This adheres to the methodology behind backstage / developer hub in combination with argo etc to have the developers manage & to get an overview of their resources without having to access the clusters.

3. Why it is needed? (List the business requirements here)
Limit direct access to non-dev clusters for cluster administrators only. Today this is required for developers to view metrics.

4. List any affected packages or components.
Prometheus, thanos, openshift-monitoring & openshift-user-workload-monitoring