RH-SSO observability and monitoring

High level goals:

Defined baseline for the operational metrics
Operational metrics available based on the chosen implementation
Metrics are good enough for scale testing
Operator metrics (CRs metrics)
Logging
Prometheus and Grafana integration
Secured metrics endpoinds

Need to capitalize on the initial investigation done via https://github.com/slaskawi/keycloak-community/blob/KEYCLOAK-8288-Observability/design/observerability.md