gh-95913: Edit, sort & expand 3.11 WhatsNew Porting section

[CAM-Gerlach]

Part of #95913

This PR copyedits, sorts and fixes the syntax of the Porting section of the What's New in Python 3.11 document. In particular, it:

• Orders the list alphabetically by module, with builtins at the top
• Adds, fixes and refines Sphinx cross references
• Adds appropriate Sphinx roles and other constructs
• Tweaks the text to fix grammar/wording issues
• Uses consistent, direct phrasing for easier/quicker readability

One item was added with this PR, based on grepping the docs, and one was removed:

• The random parameter to random.shuffle being removed was added
• A C API change mistakenly included in this section was removed, and will be added to the Porting section of the C API in a followup PR

There are likely a number of others that could be found by scouring the docs and changelog in detail, but I decided it was most pragmatic to defer that at least until later.

• Issue: Edit What's New for Python 3.11 #95913

[miss-islington]

Thanks @CAM-Gerlach for the PR, and @pablogsal for merging it 🌮🎉.. I'm working now to backport this PR to: 3.11.
🐍🍒⛏🤖

[bedevere-bot]

GH-98595 is a backport of this pull request to the 3.11 branch.