Exclude etcd readiness checks from /readyz to ignore temporary etcd h…

…iccups

Explicitly exclude etcd and etcd-readiness checks (OCPBUGS-48177)
and have etcd operator take responsibility for properly reporting etcd readiness.
Justification: kube-apiserver instances get removed from a load balancer when etcd starts
to report not ready (as will KA's /readyz). Client connections can withstand etcd unreadiness
longer than the readiness timeout is. Thus, it is not necessary to drop connections
in case etcd resumes its readiness before a client connection times out naturally.

bindata/v3.11.0/openshift-apiserver/deploy.yaml

@@ -129,7 +129,7 @@ spec:
           httpGet:
             scheme: HTTPS
             port: 8443
-            path: readyz
+            path: readyz?exclude=etcd&exclude=etcd-readiness
           initialDelaySeconds: 0
           periodSeconds: 5
           timeoutSeconds: 10