redundant etcd ServiceMonitor

[lance5890]

1. we can see two etcd ServiceMonitor in ocp cluster(etcd-minimal and etcd):

openshift-etcd-operator                      etcd                                           99d
openshift-etcd-operator                      etcd-minimal                                   99d
openshift-etcd-operator                      etcd-operator                                  99d
openshift-monitoring                         alertmanager-main                              99d
openshift-monitoring                         cluster-monitoring-operator                    99d
openshift-monitoring                         kube-state-metrics                             99d
openshift-monitoring                         kubelet                                        99d
openshift-monitoring                         metrics-server                                 99d
openshift-monitoring                         node-exporter                                  99d
openshift-monitoring                         openshift-state-metrics                        99d
openshift-monitoring                         prometheus-k8s                                 99d
openshift-monitoring                         prometheus-operator                            99d
openshift-monitoring                         thanos-querier                                 99d
openshift-monitoring                         thanos-sidecar                                 99d

2. this may be related to MON-669: Remove etcd ServiceMonitors management code as they'll be no… #2039 and MON-669: Add etcd ServiceMonitor, before that was managed by cluster-… cluster-etcd-operator#1070

[lance5890]

openshift/cluster-etcd-operator#1499

[lance5890]

@machine424