Fix merge request list icon alignment in Safari

What does this MR do and why?

• Fix merge request list icon alignment in Safari (branch and milestone)
• Hide some metadata on mobile to match issues list

Screenshots or screen recordings

Before	After

How to set up and validate locally

In Safari --> project > merge requests list

Links

• ✂️ UX Paper Cuts 17.3 → Dark mode - Design Support (#452231 - closed)