应用: 快手
任务: 打开快手，去“关注”频道，找到周同学的视频，取消关注
操作步骤:
step_id: 0
action: CLICK
step_id: 1
action: CLICK
step_id: 2
action: CLICK
step_id: 3
action: CLICK
step_id: 4
action: CLICK
step_id: 5
action: CLICK
step_id: 6
action: CLICK
step_id: 7
action: STOP