Bump RC overlay to contain v0.5.0 of driver rc

Author: davidz627

deploy/kubernetes/overlays/prow-gke-release-staging-rc/kustomization.yaml

@@ -5,10 +5,10 @@ bases:
 images:
 - name: gcr.io/gke-release/gcp-compute-persistent-disk-csi-driver
   newName: gcr.io/gke-release-staging/gcp-compute-persistent-disk-csi-driver
-  newTag: "v0.4.0-gke.0"
+  newTag: "v0.5.0-rc1"
 - name: gcr.io/gke-release/csi-provisioner
   newName: gcr.io/gke-release-staging/csi-provisioner
-  newTag: "v1.2.0-rc1"
+  newTag: "v1.2.0-gke.0"
 - name: gcr.io/gke-release/csi-attacher
   newName: gcr.io/gke-release-staging/csi-attacher
   newTag: "v1.1.0-gke.0"