feat(build/debian): Make running unit tests configurable (#1837)
feat(build/debian): Make running unit tests configurable (#1837)

I switched from `-PskipTests` to `-x test` because the former
builds the tests, but doesn't run them, while the latter skips building
them entirely.
duftler/spinnaker,skim1420/spinnaker,ewiseblatt/spinnaker,jtk54/spinnaker,spinnaker/spinnaker,duftler/spinnaker,skim1420/spinnaker,ewiseblatt/spinnaker,spinnaker/spinnaker,ewiseblatt/spinnaker,jtk54/spinnaker,jtk54/spinnaker,spinnaker/spinnaker,duftler/spinnaker,duftler/spinnaker,spinnaker/spinnaker,skim1420/spinnaker,skim1420/spinnaker,ewiseblatt/spinnaker