Upgrade: always start CA
Some CA upgrade steps in upgrader requires running CA. We have to always
start CA and wait for running status using http, because systemd may
return false positive result that CA is running even if CA is just
starting and unable to serve.
https://fedorahosted.org/freeipa/ticket/5868
Reviewed-By: Stanislav Laznicka <slaznick@redhat.com>