ci: GitLab Pages transition – Merge Request Pipelines

ci: Run jobs on Merge Request pipelines as well

We start executing the following jobs on merge request pipelines as well: build, test, code_quality and browser_performance. This can be done with a when: always which overrides the predefined rules. All of those jobs are supposed to run on the default branch and MRs.

Additionally we can now import the MR workflow of untamper-my-lockfile and make Danger run only on MRs.

ci: Move review job from Branch to MR pipelines

This one was a little trickier. The review jobs use the branch name CI_COMMIT_REF_NAME in branch pipelines for defining the branch URL. This variable is not set in MR pipelines, so we need to assign some value to that variable. Luckily CI_MERGE_REQUEST_SOURCE_BRANCH_NAME should have the same meaning with regards to the review pipelines.

ci: Turn off Branch pipelines for MRs

All the important jobs are now part of the MR pipeline, so we can move over to utilizing MR pipelines only.