chore(ci): improve GitLab <-> Jenkins contributor experience

2 aspects:

1. Jaroslava asked me if we could have always in the test-pipelines the MR ID / branch name in the run description
2. Discussing w/ Laurent: for him, one tedious step is to identify the failing tests (blue ocean)
   1. Here 1st draft is just the list
   2. we could have an hyperlink to the artifact zip file??

In documentation since it will only be tested once it's merged into develop