gh-95913: Edit & expand Deprecated section of 3.11 WhatsNew

[CAM-Gerlach]

Part of #95913

This PR copyedits, Sphinxifies, organizes and formats the Deprecated (Python) section in the Python 3.11 What's New. Specifically, it:

• Organizes the section from a long, flat, essentially arbitrary list of items to be ordered by Language/Builtin deprecations, then whole Module deprecation, and finally deprecations in the stdlib, sorted alphabetically. This puts the broader-reaching changes nearer the top and makes it much easier for readers to navigate and find particular areas/deprecations they are interested in.
• Formats the listing of PEP 594-removed modules from a long thin bulleted list to a table, to take up much less space while being easier to skim at a glance
• Tweaks the text to fix grammar and phrasing errors and issues
• Fixes and enhances the Sphinx cross-references and reST syntax used

Also, searching through deprecation warnings in the docs, I found one set of deprecations that weren't documented in the What's New, and did so:

• importlib.resources deprecated its original set of functions added in 3.7 and supplanted by improved alternatives in 3.9. However, that hadn't been mentioned in the What's New anywhere I could find, so I added a short description and enumerated the relevant functions.

There may be more in the changelog that aren't properly documented in the docs, but if so that can wait for a followup.

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

[jaraco]

Looks great. Thanks for taking the time to do this work. Did I miss an expected step when enacting the deprecation, or is this process working as expected?

[CAM-Gerlach]

Did I miss an expected step when enacting the deprecation, or is this process working as expected?

The RMs are the ultimate authority, and I'm no authority at all, but at least nowadays, per the devguide and in general practice, it seems the What's New entry is supposed to be written as part of the deprecation PR. This it ensures it is prompt, accurate and doesn't fall through the cracks. I believe in the past, though, this may not have always been the case (based on the comments in the What's New document), and there was more responsibility on the RMs to trawl through the Changelog and write up items they thought were significant enough.

In any case, thanks to the use of the deprecated/deprecated-removed directive and detailed-enough documentation, I was able to find and write it without too much trouble.

[JelleZijlstra]

Looks good, one wording suggestion

[miss-islington]

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

[bedevere-bot]

GH-98598 is a backport of this pull request to the 3.11 branch.