Comment 10 for bug 1778936

Finally I could verify the fix works well and fixes the issue.

We are building core18 image using the snap which has systemd from proposed.

Steps to validate:

1. build core18 snap using proposed
  > git clone -b master https://git.launchpad.net/snap-core18
  > cd snap-core18
  > sed -i -e 's/current/pending/g' Makefile
  > sudo snapcraft
2. prepare test
  > git clone https://github.com/sergiocazzolato/snapd.git
  > git checkout tests-validate-lp-1778936
  > cd snapd
  > < copy the core18_18_amd64.snad to tests/lib/ directory >
3. run the tests
  > spread -debug google:ubuntu-core-18-64:tests/main/interfaces-hostname-control