Update window.angular is undefined error.

Currently the error is

window.angular is undefined. This could be either because this is a non-angular page or because your test involves client-side navigation. Currently the AngularJS Library is not designed to wait in such situations. Instead you should explicitly call the "Wait For Angular" keyword.

For the case where test involves client-side navigation it gives ok information about why one is getting this error (Library is not designed to wait in such situations) and what to do (you should explicitly call the "Wait For Angular" keyword). But for the case where this is a non-angular page we could and should give a hint as to what to do in this case; such as use the ignore implicit angular wait functionality.

定位错误文本 window.angular is undefined 的来源。更新针对非 Angular 页面 的指南，以提及 ignore implicit angular wait 功能，同时保留现有的客户端导航指南，然后验证最终的错误消息。