Prevent channel from vertically growing when containing facepile (#6439)

Previously at UI font size of 20
 - User-less channel: 28 px tall
 - Occupied channel: 30 px tall
 
Now, still at UI font size 20:
 - User-less channel: 30 px tall
 - Occupied channel: 30 px tall

Release Notes:

- Fixed an issue where a channel would grow in height while showing
participant avatars.
569bb687beJulia committed on 1/24/2024, 9:17:25 PM· committed by GitHubparents4ac30959bc968e
1 file changedLine totals unavailable