docs(eslint-plugin): add Deprecating Formatting Rules blog post

[JoshuaKGoldberg]

PR Checklist

• Addresses an existing open issue: fixes Docs: Add quick blog post about deprecating formatting rules #8115
• That issue was marked as accepting prs
• Steps in Contributing were taken

Overview

Summarizes why we're doing this and links to the ESLint blog post + ESLint Stylistic docs as well.

Also includes a fix to the rule replacements: I'd forgotten ts/ exists as a separate namespace from default/.

[typescript-eslint]

Thanks for the PR, @JoshuaKGoldberg!

typescript-eslint is a 100% community driven project, and we are incredibly grateful that you are contributing to that community.

The core maintainers work on this in their personal time, so please understand that it may not be possible for them to review your work immediately.

Thanks again!

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[JoshuaKGoldberg]

cc @antfu @typescript-eslint/triage-team - I wish I'd thought to write this post alongside #8072/#8073. Ah well. I've set a reminder to merge this PR in on Monday before our scheduled weekly release. But please do yell at me if anything's off - even if you don't have time till after then. 🙂

[Josh-Cena]

Content looks great; not sure if the code change should be a separate PR but no strong feelings

[auvred]

Nice post!

I just found a few typos

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By the way, maybe this has already been discussed somewhere, but I missed it:
What about no-extra-semi rule? It's classified as suggestion rather than layout, but it's already a part of eslint-stylistic

Shouldn't we deprecate it as well? Because otherwise it will be duplicated in both ts-eslint and eslint-stylistic

[Josh-Cena]

I asked a while ago privately; I think Brad is in favor of removing it too :)

[JoshuaKGoldberg]

if the code change should be a separate PR

Heh yeah in theory maybe. But it's all going to ship at the same time. And I think this only impacts documentation anyhow.

[antfu]

Thank you! And Merry Christmas to you all!