nofirewall option (again) not working reliably (with 9.xx)

I am observing a race condition in disabling the firewall, very similar to #197 (closed).

While there was a fix committed via f04f6fe8, this part of the code (systemd unit) was changed again with c15d70c5 removing the change to the list of units to start "before".

Using rapid turnover of 10 or 15 VMs I can trigger this issue on a few attempts with then one or two of the machines. So it's definitely a race condition, not a solid failure.