* Add support for nested /etc subvolumes
* Log combustion-prepare.service to journal+console
* CI: Verify combustion runs only on the first boot
* CI: Add some missing SYSTEMD_IGNORE_CHROOT=1 to poweroff calls
* CI: Add a test with Minimal-VM
* Silence stderr of grep in /proc/*/mountinfo
OBS-URL: https://build.opensuse.org/package/show/devel:kubic:ignition/combustion?expand=0&rev=69
