base: replace PEP 541 link with user documentation link

[woodruffw]

To keep things balanced between the different columns, I've removed the link to PEP 541 and replaced it with a link to the user docs.

This has the downside of removing a link to the index's name retention polcies. However, I think there are two possible resolutions here:

1. Add the retention policies within the user docs (i.e. by copying them from the PEP and adding a "living" banner to the PEP, similar to other packaging PEPs)
2. Add the retention policies to https://policies.python.org (under the PyPI group) instead, since they're conceptually related to the other policies (AUP, T&C).

Curious what others think about either of the above 🙂

Closes #17959.

[miketheman]

I'm generally in favor of moving away from calling things a "PEP 541 request" and codifying it in a Policy, thus allowing further evolution of the policy and departing from the PEP number.

Not to increase scope too heavily, but that effort should be paired with updates to pypi/support tracker and other places where the policy is mentioned.

[woodruffw]

I'm generally in favor of moving away from calling things a "PEP 541 request" and codifying it in a Policy, thus allowing further evolution of the policy and departing from the PEP number.

Sounds good! In that case what I'll do is copy the policy bits of PEP 541 into a new PR against policies.python.org, which will then be a blocker before landing this 🙂

Not to increase scope too heavily, but that effort should be paired with updates to pypi/support tracker and other places where the policy is mentioned.

I can do a survey of these points.