Draft: Run test build in OBS for "proposed-updates" branches

Currently the proposed-updates branches (i.e. those branches which are automatically being updated from upstream) are only built as source packages and no test binary is built in the merge request context. This means that we don't check if an automatically imported package update can be built; the only binary build is completed after the merge! Let's enable test builds of imported packages pre-merge to not let any build failures on import slip through the cracks and require manual work later.

Signed-off-by: Christopher Obbard chris.obbard@collabora.com