Save user @-mention autocomplete results when commenting

Everyone can contribute. Help move this issue forward while earning points, leveling up and collecting rewards.

• Work on this issue
• Close this issue

Identified in gitlab-design#1644 (closed).

When commenting, try to save the user @-mention autocomplete results to avoid re-requests. Currently requests for the same search results are repeated, even though those requests have been already made in the current session, in different comment textareas.

CleanShot_20211214144950