PLEASE NOTE THAT THIS DIFF AND SUBSEQUENT DIFFS IN THIS STACK WILL NOT BE LANDED UNTIL MORE OF THE REDESIGN IS READY SINCE THIS WILL CAUSE REGRESSIONS IN PROD
This diff updates the ThreadMember component so that it matches the new UI redesign. This diff also resolves an issue where long usernames were not properly truncating
For context here is what the thread member component looks like on figma:
Linear task: https://linear.app/comm/issue/ENG-4161/additional-empty-spaces-between-users-on-members-list
Depends on D10922