Add docs about VIRTUAL_ENV.

[huxuan]

Add docs about VIRTUAL_ENV.

[frostming]

Maybe we can add a section Use PDM in ReadTheDocs just like Use PDM in Continuous Integration in the Advanced Usage?

This is a trick in readthedocs, and I think it applies to similar tools which prefers venv. A Q&A on the GitHub discussions also works for me.

[frostming]

It is more related to readthedocs, and stackoverflow may be a better place for this.

[huxuan]

I have to admit I searched a lot on the Internet and did not find any useful reference, the keywords I used are somthing like pdm readthedocs virtual environments. I even asked ChatGPT but still get no easy solution.

Until then I realized pdm project itself is integrated with ReadTheDocs, too. That is the best solution I have ever found including the asdf part.

Maybe we can add a section Use PDM in ReadTheDocs just like Use PDM in Continuous Integration in the Advanced Usage?