[k8s] ssh: Could not resolve hostname sshtest1: Temporary failure in name resolution

[aviweit]

When multiple ray clusters exist in a same kubernetes cluster and one of them is being removed by sky down then a wrong entry might be deleted from ~/.ssh/config.

This is because if finds the entry according to HostName where for Kubernetes they are identical (127.0.0.1 in case of kind, or the external ipaddress of the kubernetes cluster).