iOS `setVideoFrameDelegate` does not work as expected.

[vince-hz]

I want to do background removal. So I try to modify video raw data by myself. I download the project with commit hash '0ec9b443b880d7ccae058c6adfd2f1ca4d77e8be'. After setup, I clicked the 'Raw Video Data' button on the main screen. Then I join a channel successfully. But the onCaptureVideoFrame: function was not called as expected. My device is iPad Air4 and iOS version 17.3.1.