rook-ceph: pin toolbox image to ceph v19.2.2

The rook-ceph-cluster v1.20.0 chart floats the toolbox to its v20.2.1
(Tentacle) default; only the cluster daemon image was pinned to Squid
v19.2.2. After the qua recovery the rescheduled toolbox pod came up on
v20.2.1. Pin toolbox.image to match the daemons and the standing
do-not-run-v20 note.

Author: tillo

rook-ceph-cluster/values.yml

@@ -30,6 +30,7 @@ configOverride: |
 
 toolbox:
   enabled: true            # `ceph -s` CLI; used by pre-reboot-guard Ceph gate
+  image: quay.io/ceph/ceph:v19.2.2   # pin to match the cluster; rook-ceph-cluster v1.20.0 floats the toolbox to its v20.2.1 (Tentacle) default otherwise (see cephVersion pin below)
 
 monitoring:
   enabled: true            # Ceph ServiceMonitor (needs ServiceMonitor CRD - present via rancher/VM)