semaphoreci was failing with:
Can't exec "tree": No such file or directory at /tmp/autopkgtest-lxc.v9oand4g/downtmp/build.TIm/src/test/udev-test.pl line 1752.
https://semaphoreci.com/systemd/systemd/branches/pull-request-16551/builds/1
apt-get -y dist-upgrade
apt-get install -y eatmydata
# The following four are needed as long as these deps are not covered by Debian's own packaging
-apt-get install -y fdisk libfdisk-dev libp11-kit-dev libssl-dev libpwquality-dev
+apt-get install -y fdisk tree libfdisk-dev libp11-kit-dev libssl-dev libpwquality-dev
apt-get purge --auto-remove -y unattended-upgrades
systemctl unmask systemd-networkd
systemctl enable systemd-networkd