Related merge requests in issue design - Restyle

This is a redesign of the list of related merge requests that one sees inside an issue detail page.

• Implement designs from gitlab-design#83 (closed)
  • Breakpoint >1200px
  • Breakpoint >992px
  • Breakpoint >768px
  • Breakpoint >0px
  • Items, states, and tooltips
  • ☝ The issue list design spec has multiple implementation notes that also apply to other states and designs.
  • ☝ This design shares a lot of things with the design for epic issues and the related issues lists. Be sure to check that out and re-use code if it makes sense.
• The list should use a container similar to the “Related issues” one.

Design

Only restyle for this issue. New elements are added in https://gitlab.com/gitlab-org/gitlab-ce/issues/51862.

• Information to display:
  • Status (open/closed/merged)
  • ID (and path?)
  • Title (link to the merge request)
  • Milestone
  • Assignees
  • Items left to allow merge (see the Items, states, and tooltips spec for full details and explanation)
  • Pipeline status