`build_usd.py` does not express `OpenImageIO` requirement of `OpenColorIO` in development branch of 26.11

https://github.com/PixarAnimationStudios/OpenUSD/commit/ca10fc609f013513134769695289641d127a368e updated the default dependencies OpenUSD supports.

OpenImageIO 3.x requires OpenColorIO but build_usd.py does not express it in its upstream dependencies.

https://github.com/PixarAnimationStudios/OpenUSD/blob/a3d77ff5e1d405b0a5080e7c9f4c6492898fb5c5/build_scripts/build_usd.py#L2621

build_usd.py will now fail if OpenImageIO is required such as when imaging tests are built.