Allow setting replicas for applicationset controller

[tossmilestone]

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Is your feature request related to a problem? Please describe.
We want to deploy the applicaset controller with more than 1 replicas to enhance the avaliblity of the controller.

Describe the solution you'd like
Add a parameter to the applicationset to set the replicas.

Describe alternatives you've considered

Additional context

[svghadi]

Hi @tossmilestone, AFAIU, the applicationset controller doesn't support scaling load across replicas. It only supports active-passive HA. Is this what you are looking for?