Steps to remove RHACM operator and related resources properly.

Issue

• Directly removed the Advanced Cluster Management for Kubernetes operator from the OperatorHub without following the documented steps to remove RHACM.
• Namespace open-cluster-management (this is the default, other name can be used while installing the operator) stuck in terminating state, with some stuck CRs.
• Alerts generating on the cluster console like:

An aggregated API v1beta1.proxy.open-cluster-management.io/default is down. It has not been available at least for the past five minutes.
An aggregated API v1beta1.webhook.certmanager.k8s.io/default is down. It has not been available at least for the past five minutes.
An aggregated API v1.admission.cluster.open-cluster-management.io/default is down. It has not been available at least for the past five 
An aggregated API v1.admission.hive.openshift.io/default is down. It has not been available at least for the past five minutes.