Startup movies using FDefaultGameMoviePlayer are not skippable using keyboard or gamepad

There are a few separate issues with user input plumbing that prevent keypresses from getting to FDefaultGameMoviePlayer during a startup video

1) In FDefaultGameMoviePlayer::WaitForMovieToFinish(), the movie widget doesn't have user focus, so keypresses don't get routed correctly.

2) Event handler SDefaultMovieBorder::OnKeyDown is not invoked when MySDefaultMovieBorder->OnKeyDown() is called

Modify FShooterGameLoadingScreenModule::StartupModule() to add
// force startup video to wait for user skip
LoadingScreen.bWaitForManualStop = true;

Launch ShooterGame (originally observed on PS4)

press any button/key to skip the video

-> startup video continues to loop despite any user keypresses