Try to add the port number to docker image

.gitlab-ci.yml

 py27-linux:
-  image: docker.idiap.ch/beat/beat.env.web:latest
+  image: docker.idiap.ch:5000/beat/beat.env.web:latest
   script:
   - /usr/local/beat/usr/bin/python bootstrap-buildout.py
   - ./bin/buildout