1. Proposed title of this feature request

Limit the metrics exposed by Custom Metrics Autoscaler operator
2. What is the nature and description of the request?

It would be great to be able to select which of the metrics that the CMA generates are exposed.
3. Why does the customer need this? (List the business requirements here)

My customer, with `remote_write`enabled in Prometheus, is receiving around 9000 metrics every 10 minutes. Most of the metrics are careless, and it is adding a lot of load.
4. List any affected packages or components.

Custom Metrics Autoscaler