Improve sorting assignee list in merge requests

Problem to solve

Currently it seems the assignee list in merge requests is sorted alphabetically. When creating a merge request I always have to scroll down the list to find the one or two assignees I tend to use most.

Further details

Since in most projects you tend to assign the same people in most merge requests, it would make sense for the list to sort them on top to streamline merge request creation.

Proposal

Assignees should be sorted by number of times they were assigned in that project. It might even make sense to have a separate shortcut near the dropdown with the most common assignee, much as is done now with the Assign to me link.

What does success look like, and how can we measure that?

Less time spent selecting an assignee for a new merge request.