iOS-Tagent + XCode 13.1 + iOS 15.1 error and solution

If you use iOS-Tagent and are facing one of the following problems:

1. No response after clicking on the connect button in Airtest-IDE for iOS devices.
2. Use the command-line tool of Airtest directly and see errors similar to `wda.exceptions.WDAUnknownError: WDARequestError`

Try to use the appium version of the WebDriverAgent [Appium WebDriverAgent](https://github.com/appium/WebDriverAgent). The way to use it is very similar to iOS-Tagent. Just clone the repository, open it in XCode, change the Signing, choose your device as the destination and click on test.

Notice that after running the agent app, you might still need to wait for up to 5 minutes to get the screenshots. My assumption is that the WebDriverAgent needs time to initialize.

Notice that [http://127.0.0.1:8100/inspector](http://127.0.0.1:8100/inspector) was removed by appium. So it is normal to see error if you visit the link. This won't have any effect on Airtest.

The way to execute airtest using the terminal:
```
/Applications/AirtestIDE.app/Contents/MacOS/AirtestIDE runner ./your_project.air --device ios:///http://127.0.0.1:8100 --log
```

**Fair warning: Even the Appium could be unresponsive after several minutes and you have to quit the agent and reconnect again. But since the repository is still actively maintained, maybe they will fix the issue.**