feat(helm): support different replicaCount

[gforien]

SUMMARY

We want to configure a different replicaCount for supersetNode and supersetWorker deployments, as they do not undergo the same load.

The replicaCount should be configurable on a per component level instead of globally for the whole chart.

TESTING INSTRUCTIONS

Templating can be verified manually with helm template

• helm lint
• helm3 template superset-release .
• Check that the new values are now required

❯ helm template superset-release .  --set supersetWorker.replicaCount=null --set supersetNode.replicaCount=null

Error: values don't meet the specifications of the schema(s) in the following chart(s):
superset:
- supersetWorker: replicaCount is required
- supersetNode: replicaCount is required

ADDITIONAL INFORMATION

• Has associated issue: [Helm chart] Support different replicaCount, nodeselector, tolerations, affinity and resources for each component #19250
• 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

[github-actions]

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[craig-rueda]

Just make a new value under supersetWorker and use it here (default of the current replicaCount)

[gforien]

Ok so I did

• remove replicaCount in the values, in the schema, and in the array of required values
• add supersetNode.replicaCount and supersetWorker.replicaCount in the values, in the schema, and in the array of required values
• edit the "Running on Kubernetes" doc
• bump version to 0.7.0

[craig-rueda]

Same comment as above