Upgrade to Unreal Engine 5.1

[xuelongmu]

I think the tutorial project should be upgraded to 5.1. Unreal Engine 5.0 has some pretty glaring bugs in VR, and 5.1 has better stability and performance. There are some graphical glitches and stutters as well, that are hopefully improved in the newer version.

This shouldn't be a big technical lift, as the project can theoretically be upgraded in-place. However it would also be an opportunity to do a polish pass on performance and visual quality on the project as a whole.

cc @CesiumBen @LisaBosCesium