OBS container_post_run hook to wrap a kiwi or docker image in an rpm package.
This package should be required by the Build Service project's meta prjconf, so that the container_post_run hook is present in the container image and gets executed at the end of the image build. It will then build an rpm which contains the newly-produced image from kiwi/docker (using image.spec.in), and place the rpm in the correct location that it becomes an additional build artefact.