ncm-cdp: hotfix for unittests 

due to new CAF::Service command generation for systemd, the cdp unittest fails, blocking all other jenkins builds
Won't merge as it is.

The correct fix is to rely on a new enough version of the build tools, which should expose an API for setting the service variant, as you can see in quattor/maven-tools#18 . Also, using `service cdp-listend restart` would be less surprising to other developers who don't have access to systemd hosts yet.

However, somebody or something pushed with `--force`, and that PR went away.

I'll have to do the same thing myself next week. In the mean time I'll hold this.