etcd has support for client-cert-auth, which can be configured via the flag `--ca-file`,
when that is enabled, all the client requests must present with a client certificate,
however, the current component status check uses a single transport for all of the checks,
this is wrong, the checks should be different for each of different component, and make
each of them use different transport(tls configurations).
Kubernetes-commit: b1040171b68217dccb617de85defa4a5063c638b