9e150fe82c
This will fetch and call the build_usd.py build helper for OpenUSD and build within the MuJoCo _deps folder. Simplifying the build process for MuJoCo with USD. Users can still provide their own USD build, but must now do so via pxr_DIR. PiperOrigin-RevId: 846735578 Change-Id: I0da7eb2da6465e2d518084340e762bf370adb6d5