应用: 百度网盘
任务: 启动百度网盘，浏览文件列表，下载最上面的文件
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