Yu Watanabe
18f2e9bcfa
Otherwise, all test cases that does not create/start the service emits
the following error:
```
Failed to stop test-modem-manager-mock.service: Unit test-modem-manager-mock.service not loaded.
```
Moreover, without this change, extra 'systemctl daemon-reload' is triggered after
all test cases. That's super heavy, especially when the test is running on
sanitizers.
Follow-up for abe3d570f8.