Goal:

• The observabilityclient sends a request to Prometheus to figure out the metric names every time a "query modification to add tenancy labels" is done. Some parts of Aetos have multiple of these queries (amount depends on user and is theoretically unlimited), which must be modified and so runs the modification in a loop. Currently this results in the same Prometheus API call with the same result being sent over and over.
• We need to cache the result at least for the duration of the life of each PromQLRbac object.

Acceptance Criteria:

• Change is proposed and merged