Add milestones to release blocks
What does this MR do?
Adds milestones to release blocks as described in https://gitlab.com/gitlab-org/gitlab-ce/issues/62402:
In addition, this MR converts the release_block_spec.js test from Karma to Jest.
UX specs
With no milestones associated (no visual changes):
With multiple milestones associated:
Note: the footer ("View Issues of Merge Requests in this release") is not implemented by this merge request.
Screenshots
With no milestones associated (no visual changes):
With one milestone associated:
With multiple milestones associated:
When hovering over a milestone:
Edited by Nathan Friend