opencolorio 2.3.0 build failure

[chenrui333]

👋 trying to build the latest release, but run into some build issue. The error log is as below:

error build log

  -- Could NOT find pystring (minimum version: "1.1.3", recommended version: "1.1.3")
  --    pystring_ROOT was: /opt/homebrew/opt/pystring
  CMake Error at share/cmake/macros/ocio_handle_dependency.cmake:220 (message):
    pystring is required, will abort at the end.
  -- Could NOT find minizip-ng (minimum version: "3.0.6", recommended version: "3.0.7")
  CMake Error at share/cmake/macros/ocio_handle_dependency.cmake:220 (message):
    minizip-ng is required, will abort at the end.

full build log, https://github.com/Homebrew/homebrew-core/actions/runs/6094230289/job/16535428119
relates to Homebrew/homebrew-core#141062

[remia]

Hi @chenrui333,

Thanks for the report, I noticed something similar while trying to build OCIO with OCIO_INSTALL_EXT_PACKAGES=NONE and homebrew packages, it seems this is the same thing going on here. I managed to have something working with the modifications in the last 2 commits of this PR though it probably need a bit more testing, note that I included the change from this other PR which is also needed.