Packaging >=22 no longer supports 'latest' versions, which is the version that is assigned when building the docs.
https://github.com/pytest-dev/pytest/pull/10578#issuecomment-1348249045
Also first install pytest, then `docs/en/requirements.txt`:
Installing the requirements last will honor pins of libraries
shared between pytest and the docs build.
The PDF documentation on readthedocs was missing the figures in the
fixtures reference chapter. This PR uses a Sphinx plugin that
automatically converts the checked-in SVG files to the PDF input files
that LaTeX requires.
The SVG-to-PDF conversion is done by inkscape, which gave the best
conversion among the tools I tried. However, it [does not yet
understand][href-bug] that you can write a plain `href` instead of
`xlink:href` in svg files, so I’ve had to edit the SVG files
accordingly.
[href-bug]: https://github.com/TeX-Live/luatex.git