The NKG controller should run with least privileges

[ja20222]

As a potential user of NKG that wants to run NKG on a permission restricted cluster
I want the NKG controller to run with the least privileges it needs to operate
So that I can run NKG in my permission restricted cluster.

Acceptance

• Ensure that the privileges on the pod are restricted to only what is necessary
• Ensure that RBAC permissions for the service account associated with NKG pods are restricted to only what is necessary.