In some cases, Kubernetes / OpenShift storage classes are unable to properly handle multiple availability zones and distribute the brokers / PVs across them. In such cases it would be great to be able to specify different storage class for each broker and thus drive the placement of the broker into an AZ through the storage class and through the PV. After we decouple STS from the PVs (ENTMQST-804), this should be feasible to implement. We can use similar `override` construct as we use for off-cluster access.

    overrides:
      brokers:
      - broker: 0
         - id: 0
            storageClass: hdd-eu-0
         - id: 1
            storageClass: hdd-eu-0
      - broker: 1
         - id: 0
            storageClass: hdd-eu-1
         - id: 1
            storageClass: hdd-eu-1
      - broker: 2
         - id: 0
            storageClass: hdd-eu-2
         - id: 1
            storageClass: hdd-eu-2