feat(helm): allow removal of Node & Worker replicas for custom HPA solutions

[hanslemm]

SUMMARY

This PR allows Helm deployments to use custom HPA solutions.

In my company, we don't use the Kubernetes metrics server for autoscaling, but rather Keda with Prometheus metrics. With that in mind, the current Helm deployment doesn't work for us, as the default HPA solution cannot find the metrics to autoscale.

The idea is to allow developers to specify custom HPA in their Kubernetes. To do so, it would be great if we could control the replicaCount of Worker and Node deployments, so that we can turn off the replicaCount and provide an HPA solution outside the Helm Charts.

This PR:

• Creates .Values.supersetNode.replicas.enabled bool with true as default value.
• Creates .Values.supersetWorker.replicas.enabled bool with true as default value.
• Moves .Values.supersetNode.replicaCount to .Values.supersetNode.replicas.replicaCount
• Moves .Values.supersetWorker.replicaCount to .Values.supersetNode.replicas.replicaCount
• Updates the charts of Node and Worker
  • if not [worker|node].autoscaling.enabled and [worker|node].replicas.enabled then the replicaCount logic will be applied. Any other combination will remove replicaCount.
  • By default values the replicaCount logic will be applied as autoscaling is disabled and replicas is enabled.

BEFORE/AFTER SCREENSHOTS OR ANIMATED GIF

TESTING INSTRUCTIONS

ADDITIONAL INFORMATION

• Has associated issue:
• Required feature flags:
• Changes UI
• Includes DB Migration (follow approval process in SIP-59)
  • Migration is atomic, supports rollback & is backwards-compatible
  • Confirm DB migration upgrade and downgrade tested
  • Runtime estimates and downtime expectations provided
• Introduces new feature or API
• Removes existing feature or API

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