Note: Only Company Owners, Admins and Team Admins can add or update a team's profile picture.
Web Portal
Click 'Settings' in the left hand side bar
Click 'Teams'
Find the team and click it
βNote: See this article if you need help searching for the teamUnder the general section, click 'Edit' next to the existing profile picture
Select your image from the file browser
Wait for it to upload
Your team profile picture is now updated