PEP 458: Clarify sequence of PyPI and pip integration

[brainwane]

OK'd by coauthors in Discourse conversation.

[hugovk]

This PEP is commented out of the CODEOWNERS file:

peps/.github/CODEOWNERS

Line 318 in ca6d20a

# pep-0458.txt, pep-0458-1.png

Probably because the PEP predates the CODEOWNERS file.

PEP 1 says:

Update .github/CODEOWNERS such that any co-author(s) or sponsors with write access to the PEP repository are listed for your new file. This ensures any future pull requests changing the file will be assigned to them.

Shall we add the sponsor, @ncoghlan, to CODEOWNERS for this PEP?

[CAM-Gerlach]

That would be SOP, but up to @ncoghlan if he still wants to be sponsor, or maybe better to have @dstufft , the PDP-Delegate, be sponsor instead since he's more active nowadays with regard to PyPI, AFAIK.

[hugovk]

We can update CODEOWNERS as and when, let's get this merged. Thanks!