Update etcdadm-controller to loop through all the external IPs and pass the healthcheck if etcd endpoint is connected to any of the IPs

Currently, the etcd health check fails if we add a secondary IP on an etcd VMs. The etcdadm controller finds the recently added Ip's frequency unhealthy, adds the machine to the unhealthy list, brings down the current etcd vm and goes ahead with bringing up new etcd, cp or brings down the entire cluster in case of 1 control plane.

To resolve this issue, we should loop through all the external IPs machine object have and should pass the health check if etcd is available on any of the IPs. https://github.com/aws/etcdadm-controller/blob/main/controllers/helpers.go#L159-L188

-managed-etcd secret doesn't have endpoint IP in the etcd certificate but we should make sure this change is not affecting the certificate or any other place.