Cluster Operator unavailable with 'APIServicesAvailable: "apps.openshift.io.v1" is not ready'

Issue

• The OpenShift Container Platform Cluster Operator openshift-apiserver is not available and is showing the following APIServices_Error errors:

  APIServicesAvailable: "apps.openshift.io.v1" is not ready: an attempt failed with statusCode = 503, err = the server is currently unable to handle the request
  APIServicesAvailable: "authorization.openshift.io.v1" is not ready: an attempt failed with statusCode = 503, err = the server is currently unable to handle the request
  APIServicesAvailable: "build.openshift.io.v1" is not ready: an attempt failed with statusCode = 503, err = the server is currently unable to handle the request
  APIServicesAvailable: "image.openshift.io.v1" is not ready: an attempt failed with statusCode = 503, err = the server is currently unable to handle the request
  APIServicesAvailable: "project.openshift.io.v1" is not ready: an attempt failed with statusCode = 503, err = the server is currently unable to handle the request
  APIServicesAvailable: "quota.openshift.io.v1" is not ready: an attempt failed with statusCode = 503, err = the server is currently unable to handle the request
  APIServicesAvailable: "route.openshift.io.v1" is not ready: an attempt failed with statusCode = 503, err = the server is currently unable to handle the request
  APIServicesAvailable: "security.openshift.io.v1" is not ready: an attempt failed with statusCode = 503, err = the server is currently unable to handle the request
  APIServicesAvailable: "template.openshift.io.v1" is not ready: an attempt failed with statusCode = 503, err = the server is currently unable to handle the request
  

• The OpenShift API Server (apiserver) Pod in the openshift-apiserver namespace is showing the following connection refused error messages:

  2023-06-19T07:59:22.838495962Z W0619 07:59:22.838437       1 logging.go:59] [core] [Channel #159 SubChannel #160] grpc: addrConn.createTransport failed to connect to {
  2023-06-19T07:59:22.838495962Z   "Addr": "10.140.20.23:2379",
  2023-06-19T07:59:22.838495962Z   "ServerName": "10.140.20.23",
  2023-06-19T07:59:22.838495962Z   "Attributes": null,
  2023-06-19T07:59:22.838495962Z   "BalancerAttributes": null, 
  2023-06-19T07:59:22.838495962Z   "Type": 0,
  2023-06-19T07:59:22.838495962Z   "Metadata": null
  2023-06-19T07:59:22.838495962Z }. Err: connection error: desc = "transport: Error while dialing dial tcp 10.140.20.23:2379: connect: connection refused"
  

• The etcd Pods show error messages similar to the following:

  2023-06-19T09:34:37.366653439Z {"level":"warn","ts":"2023-06-19T09:34:37.366Z","caller":"rafthttp/http.go:394","msg":"rejected stream from remote peer because it was removed","local-member-id":"ed898fb22814c213","remote-peer-id-stream-handler":"fd898fb22814c212","remote-peer-id-from":"32b626d55668f0af"}
  2023-06-19T09:34:37.367468970Z {"level":"warn","ts":"2023-06-19T09:34:37.367Z","caller":"rafthttp/http.go:394","msg":"rejected stream from remote peer because it was removed","local-member-id":"ed898fb22814c213","remote-peer-id-stream-handler":"fd898fb22814c212","remote-peer-id-from":"32b626d55668f0af"}