grafana-dashboard-cluster-logging should be deleted once clusterlogging/instance was removed

Description of problem:

grafana-dashboard-cluster-logging should be deleted once clusterlogging/instance was removed

How reproducible:

Always

Steps to Reproduce:

1) deploy clusterlogging/instance

2) Check the grafana-dashboard config

oc get cm grafana-dashboard-cluster-logging -n openshift-config-managed

oc get cm grafana-dashboard-elasticsearch -n openshift-config-managed

3) remove the clusterlogging/instance

4) Check the grafana-dashboard config again

Actual results:

grafana-dashboard-cluster-logging is perserved

grafana-dashboard-elasticsearch was deleted

Expected results:

Both grafana-dashboard-cluster-logging and grafana-dashboard-elasticsearch should be  deleted