gh-115426: Fix the socket object close() cross-references

[jang-hs]

The socket object's close() is documented as a method, but the three
cross-references to it resolved to the module-level socket.close(fd)
function instead, so clicking any of them landed on the wrong object.

close is the only name that is both a module-level function (added in 3.7)
and a socket method, and the Python domain matches <module>.<target> before
the class-scoped name, so :meth:socket.close hit the function and won. Every other method reference on the page has no module-level homonym and resolves correctly, which is probably why this went unnoticed. Qualifying the target as `socket.socket.close` matches the neighbouring `:meth:`~socket.socket.ioctl and :meth:~socket.socket.shutdown``.

Two of the three now render as close() rather than socket.close(). That
seemed right rather than incidental, since socket.close() is literally the
name of the fd function and close() is how every other socket method renders
on the page. The bare :meth:close`` references inside close()'s own
description are left alone: Sphinx drops the link on a self-reference, which I
checked is independent of this bug.

@zevisert diagnosed this correctly when filing the issue in 2024. I built the
docs to confirm the link targets before and after, with no change to the
nitpick warning count for socket.rst.

Drafted with AI assistance, reviewed and verified locally before opening.

• Issue: Socket documentation links socket object .close methods to module level socket.close(fd) #115426

[python-cla-bot]

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[miss-islington-app]

Thanks @jang-hs for the PR, and @StanFromIreland for merging it 🌮🎉.. I'm working now to backport this PR to: 3.13, 3.14, 3.15.
🐍🍒⛏🤖

[bedevere-app]

GH-157330 is a backport of this pull request to the 3.15 branch.

[bedevere-app]

GH-157331 is a backport of this pull request to the 3.14 branch.

[bedevere-app]

GH-157332 is a backport of this pull request to the 3.13 branch.