[FLINK-38552] [Helm] Fix FlinkStateSnapshot when operator's namespace not in watchNamespaces

[MaksimAniskov]

This change fixes support for FlinkStateSnapshot CRDs getting disabled if the operator deployed using the Helm chart and the operator's namespace not listed in watchNamespaces value.

The operator's isCrdInstalled check requires list permission for flinkstatesnaphots verb in the operator's namespace.

When the namespace listed in watchNamespaces, lines 24-32 of helm/flink-kubernetes-operator/templates/rbac/role.yaml create the Kubernetes role with necessary permission as defined in helm/flink-kubernetes-operator/templates/rbac/_helpers.tpl

When the operator's namespace isn't in watchNamespaces, another part of the template defines the role. This part should also define the permission.

[mateczagany]

Thank you for this fix, @MaksimAniskov

This check was added when introducing FlinkStateSnapshot in release 1.10 to make sure that we don't break existing deployments where the CRD is not yet installed by creating a controller. I think it should be safe to remove this check altogether in the next release of 1.14, so the Helm chart change might not even be needed. WDYT?

[MaksimAniskov]

@mateczagany I saw that isCrdInstalled is scheduled for deleting. If the check gets deleted, that will solve the issue.