Fix an issue with the OCIO’s Linux container images that have OpenSSL under 1.1.1.

If the container images are updated with OpenSSL 1.1.1+, the restriction on

urllib3 version <2 can be removed.

urllib3<2

The builds for documentation fails with <0.18.0

docutils>=0.18.1 sphinx<=7.1.2 six testresources recommonmark sphinx-press-theme sphinx-tabs breathe