Docs: Remove outdated and misleading Poetry guide

[juantocamidokura]

Fixes #9771

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📚 Documentation previews 📚

• User's documentation (docs): https://docs--9794.org.readthedocs.build/en/9794/

• Developer's documentation (dev): https://dev--9794.org.readthedocs.build/en/9794/

[benjaoming]

Thanks!

You'll need to also remove the reference in docs/user/guides/developers.rst

[benjaoming]

LGTM 👍

[ericholscher]

We should likely update this page with some pointers, or at least put in a redirect to some content that we have around this. It's a common topic, so where should we be sending people who need this type of content?

[benjaoming]

@ericholscher how about we do a redirect to the configuration example? https://docs.readthedocs.io/en/stable/build-customization.html#install-dependencies-with-poetry (secondary question: are redirects with anchors supported?)

[benjaoming]

@ericholscher in case you agree that we can do this without a placeholder, the redirect is ready 👍

[ericholscher]

That redirect works 👍

[benjaoming]

Redirect tested 👍

https://docs.readthedocs.io/en/latest/guides/poetry.html