开始可以获取到元素，后面无法获取到元素，报错信息如下：
[sessionCapabilities()] Error response status: 10, , StaleElementReference - An element command failed because the referenced element is no longer attached to the DOM. Selenium error: The previously found element "Application 'com.apple.springboard'" is not present in the current view anymore. Make sure the application UI has the expected state. Original error: Error getting m
ain window kAXErrorServerNotFound
