Tests in this directory rely on an ability to spawn ctrld daemon on
remote node(s) over ssh and close the ssh connection. On systems with
systemd version >= 230 all user processes started in one session are
killed on logout, even when they were detached using daemon(3).
To workaround this issue, change "KillUserProcesses" back to "no" in
logind.conf and restart systemd-logind service (systemctl reload
systemd-logind.service).
https://github.com/systemd/systemd/blob/3a74d4fc90cb322a4784a3515bef7118c8f8c5ba/NEWS#L29.