应用: 腾讯会议
任务: 打开腾讯会议，使用会议码“999-888-777”加入会议
操作步骤:
step_id: 0
action: CLICK
step_id: 1
action: CLICK
step_id: 2
action: CLICK
step_id: 3
action: TYPE
type_text: 999-888-777
step_id: 4
action: CLICK
step_id: 5
action: CLICK