Add Horizontal Pod Autoscaling to Common Chart

[jacaudi]

Details

Describe the solution you'd like:

I would like to an option to configure HPA for deployments and statefulsets. I would like to start with metrics server based metrics and iterate other sources later.

Anything else you would like to add:

I would like to collaborate with you and find the best way to implement this. I just need to know if you would like me to wait until the 4.0.0 release, or if you want to add it to the 4.0.0 release. Thank you!

Additional Information:

Each HPA configuration would be specific to each controller. Maybe something like this:

controllers:
  example:
    type: statefulset
    hpa:
      min: 1
      max: 10
      metrics:
        - cpu
          utilization: 50
        - memory
           utilization: 80
    containers:
      example:
        image:

[koslowdavida]

If picked up I would like to ask for a carve out in the hpa scaleTargetRef field validation for argo rollout users please:

spec:
  scaleTargetRef:
    apiVersion: argoproj.io/v1alpha1
    kind: Rollout
    name: example-rollout

[Preisschild]

If someone wants to implement this, copying the PDB implemention would be easy i think