Show the position of a merge request in a Merge Train
Problem to solve
In order to let users know where a merge request is in a merge train, we need to inform in the UI of a merge request position once it enters the merge train.
Acceptance Criteria
- Given no previous merge train exists: If the pipeline succeeds, the merge request will automatically be merged. The merge request will be placed in position 1 in the Merge train and a helper text is added under the pipeline block.
- Given a merge train exists: The new pipeline won't start until the previous one finishes. If the pipeline succeeds, the merge request will automatically be merged. The merge request will be placed in position
nin the Merge Train and a helper text is added under the pipeline block.
Full prototype can be see on https://gitlab.com/gitlab-org/gitlab-ee/issues/9186