ci: Set machine-id for dbus

Systemd does not exist in the docker file. So we just set an machine-id,
which the dbus-daemon can use to start a session.

Signed-off-by: Sven Sager <s.sager@kunbus.com>

.gitlab-ci.yml

@@ -28,6 +28,7 @@ run_tests:
   script:
     - apt-get update
     - apt-get -y install dbus libgirepository1.0-dev
+    - dbus-uuidgen --ensure=/etc/machine-id
     - pip install -r requirements.txt
     - PYTHONPATH=src pytest -v --junitxml=report.xml --cov=src --cov-report term --cov-report xml:coverage.xml
   coverage: '/(?i)total.*? (100(?:\.0+)?\%|[1-9]?\d(?:\.\d+)?\%)$/'