应用: 拼多多
任务: 打开拼多多，搜索‘T恤’，点击第三条商品，选择尺码为‘M’
操作步骤:
step_id: 0
action: CLICK
step_id: 1
action: CLICK
step_id: 2
action: TYPE
type_text: T恤
step_id: 3
action: CLICK
step_id: 4
action: CLICK