Running systemctl over the new ssh driver fails

[afbjorklund]

Systemd returns an error code (!) for all kinds of status-like commands,
and the new SSH driver doesn't like when the command it executes fails.

This means that we cannot run things like "is-active" anymore:

$ minikube docker-env

💣  Error getting service status: ssh command error:
command : sudo systemctl is-active docker
err     : Process exited with status 3
output  : inactive


😿  Sorry that minikube crashed. If this was unexpected, we would love to hear from you:
👉  https://github.com/kubernetes/minikube/issues/new

Or at least not when it returns inactive, still OK with active.

       is-active PATTERN...
           Check whether any of the specified units are active (i.e. running). Returns an exit code 0 if at least one is active, or non-zero otherwise. Unless
           --quiet is specified, this will also print the current unit state to standard output.