Leave a Team
Click your avatar and choose My profile from the menu:
On your Profile sidebar click Teams:
Locate the team you want to leave and click next to that team:
Choose Request to leave.
If you have admnistrative rights over this team, click Revoke.
Choose the date you want to leave and click Request:
You request will be sent to the Team Admin. As soon as the Team Admin approves it, you'll be removed from the team and will get a notification in Chats.
If you have admnistrative rights over this team, you don't need approval, and your membership will be revoked on the specified date. Note that your admnistrative rights will remain intact even after you remove yourself from the team.