This is a two-steps process. First a private
tc build is triggered through the gitlab API.
This job will build both tc and assignment
(which has a dependency on it). Once this jobs
has finished, it publishes the HTML pages as an
artifact and tigger back an assignment build.
This last build will grab HTML pages and build
the Docker that will handle the whole website for
assigment.

* .gitlab-ci.yml, Dockerfile: Here.