INC3028909: add systemctl tests

This change adds two new tests to confirm that images released comply to the same checks that the CERN collectd-systemd currently report on.

• https://github.com/cernops/collectd-systemd#systemd-needreloadboolean-needdaemonreload
• https://github.com/cernops/collectd-systemd#systemd-systemd-stateboolean-running