ci: Use journalctl to get minion logs
ci: Use journalctl to get minion logs

Before, our minion test only retrieved the logs of the most recent
instance of the minion container. Thus, when a minion container died and
was restarted, we didn't have the logs of the crashed minion.

kklin/quilt,tejasmanohar/quilt,PenguinToast/quilt,kelda/kelda,LuiseV/quilt,kklin/quilt,quilt/quilt,mmussomele/quilt,LuiseV/quilt,PenguinToast/quilt,kayousterhout/quilt,stevenlin598/quilt,kelda/kelda,LuiseV/quilt,ejj/quilt-dev,stevenlin598/quilt,kayousterhout/quilt,mmussomele/quilt,NetSys/quilt,quilt/quilt,mmussomele/quilt,kklin/quilt,PenguinToast/quilt,kayousterhout/quilt,PenguinToast/quilt,kklin/kelda,mmussomele/quilt,kklin/kelda,stevenlin598/quilt,ejj/quilt-dev,kklin/quilt,kayousterhout/quilt,mmussomele/quilt,kklin/kelda,PenguinToast/quilt,ejj/quilt-dev,kklin/kelda,stevenlin598/quilt,NetSys/quilt,kelda/kelda,mmussomele/quilt,ejj/quilt-dev,LuiseV/quilt,quilt/quilt,tejasmanohar/quilt,LuiseV/quilt,NetSys/quilt,stevenlin598/quilt,kelda/kelda,tejasmanohar/quilt,tejasmanohar/quilt,NetSys/quilt,quilt/quilt,NetSys/quilt,stevenlin598/quilt