移除群的观察者通知。自己退群,群被解散,自己被踢出群时,会收到该通知 observer 观察者, 参数为被移除的群资料,此时群的isMyTeam接口返回false
Stream<List<NIMTeam>> get onTeamListRemove => TeamServicePlatform.instance.onTeamListRemove.stream;