ci: let Rook deploy a Ceph Tentacle cluster

Signed-off-by: Niels de Vos <ndevos@ibm.com>

Author: nixpanic

build.env

@@ -58,7 +58,7 @@ CHANGE_MINIKUBE_NONE_USER=true
 # Rook options
 ROOK_VERSION=v1.18.4
 # Provide ceph image path
-ROOK_CEPH_CLUSTER_IMAGE=quay.io/ceph/ceph:v19.2.2
+ROOK_CEPH_CLUSTER_IMAGE=quay.io/ceph/ceph:v20
 
 # CSI sidecar version
 K8S_IMAGE_REPO=gcr.io/k8s-staging-sig-storage