(kube-rbac-proxy): make requests and limits configurable

[Obirah]

Is your feature request related to a problem? Please describe.
It is not possible to configure requests and limits for the kube-rbac-proxy sidecar container of the Istio Operator Deployment.

Describe the solution you'd like to see
A new value with proper defaults in the Helm Chart that allows me to set the resources field of the kube-rbac-proxy sidecar container.

Describe alternatives you've considered
Not setting resources is the alternative, but that leaves me with a permanent ArgoCD diff at the moment, because ArgoCD currently does not recognize the absence of the resource field as meaning the same as resources: {}.