Add dependency to dash-licenses

Add dependency to dash-licenses

This is required to run the license check using the license tool [1]
required by the Eclipse project handbook [2]:

mvn org.eclipse.dash:license-tool-plugin:license-check -Ddash.summary=DEPENDENCIES

Note: the tool still requires Java 11 hence it needs to be run in a
separate build step and is not yet integrated in the build which runs
on Java 8.

[1] https://github.com/eclipse/dash-licenses
[2] https://www.eclipse.org/projects/handbook/#ip-license-tool

Change-Id: Ib41d54de246c3c9499cc3be9f026294c39fdfd99