CI: Update include file's ref in gitlab-ci.yml when deploying changes

Add update gitlab-ci file with function to adapt the include ref to a
given revision.
Add a 'pre-commit-hook' to the update-submodule function.
Adapt deploy_gitlab_ci to use these to update the include statement in
the base project .gitlab-ci.yml to use the same ref as the submodule
is set to.

BCS 746-000646