Update documentation for helm deployment

[chilagrow]

Has the Kubernetes service name changed 🤔 ? I followed the helm deployment guide and noticed the service name was different.

kubectl get svc 
NAME                 TYPE        CLUSTER-IP     EXTERNAL-IP   PORT(S)                      AGE
kubernetes           ClusterIP   10.43.0.1      <none>        443/TCP                      21h
monitoring-service   NodePort    10.43.233.57   <none>        443:31197/TCP,80:31056/TCP   20h

[it-percona-cla]

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[Nailya]

lgtm

[Nailya]

it should be changed also for Openshift:
oc expose svc/pmm-service --port=443 should be
oc expose svc/monitoring-service --port=443