WHAT
We currently have some metrics available for Postgres/Redis instances on GCP but are missing some metrics which are required for RHOAM's alerting. In particular the following metrics should be exposed for GCP:

Postgres

• cro_postgres_cpu_utilization_average
• cro_postgres_freeable_memory_average
• cro_postgres_max_memory
• cro_postgres_free_storage_average
• cro_postgres_current_allocated_storage

Redis

• cro_redis_engine_cpu_utilization_average
• cro_redis_memory_usage_percentage_average

HOW
See the cloudmetrics controller that is used for AWS.

The GCP documentation recommends using the monitoring api https://cloud.google.com/monitoring/api/metrics and the associated package https://pkg.go.dev/cloud.google.com/go/monitoring/apiv3

Can the metric client be used to get this info from the instances.

TESTS
<List of related tests>

DONE
The above metrics are exposed by CRO