nixpkgs

b597c388 - openimageio: build with openexr 3

openimageio: build with openexr 3 ilmbase is replaced by Imath (propagated from openexr_3) See the following upstream change from 2020 on OpenEXR 3.x support: https://github.com/AcademySoftwareFoundation/OpenImageIO/commit/6313484e35765df1adf8f40c217cebc4c9d9d954#diff-40f1f520160b8fecd67891ee24b54add91856f733ece4bae0c3896adb00452af