Lack of monitor metrics

[cindy52]

Is your feature request related to a problem? Please describe.

Without any monitor metrics, it's hard to tell whether HPA operator is still running or it's successfully creating, updating and deleting a HPA.

Describe the solution you'd like to see

HPA operator should have monitor metrics including creating, updating and deleting HPA. It should also have a liveness probe and readiness probe in the helm deployment chart.

Describe alternatives you've considered

Additional context