When building unprivileged, the testuser home directory ends up owned by root:root because mkosi can't chown directories to other owners when running unprivileged. So let's fix up the testuser ownership on first boot with tmpfiles instead.
When building unprivileged, the testuser home directory ends up owned by root:root because mkosi can't chown directories to other owners when running unprivileged. So let's fix up the testuser ownership on first boot with tmpfiles instead.