Extend .default-workflow to trigger pipelines on all project branch commits

Migrated issue

Reported by: jonathan1055

Related to !2 (merged)

We now have a .default-workflow reference in Gitlab Templates. So we can use and extend this to trigger pipelines in GTD when we push directly to any of the variant branches.

This was added in gitlab_templates#3504083 (closed)

Related issue: Issue #3504083