Plugin: Bump minimum required WordPress version to 6.6

[ockham]

What?

Similar to #64126.

Bumps the "Required WP version" field to 6.6, and the "Tested up to" field to 6.7. It also updates the performance test base hash.

Why?

To reflect the current WP version, and update the minimum required version to the previous one.

I'd also like to unblock #64676 😬

How?

See https://developer.wordpress.org/block-editor/explanations/architecture/performance/#update-the-reference-commit

Testing Instructions

• CI checks should be green.
• Confirm that new commit SHA matches guidelines.

[github-actions]

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Co-authored-by: ockham <bernhard-reiter@git.wordpress.org>
Co-authored-by: ramonjd <ramonopoly@git.wordpress.org>
Co-authored-by: Mamaduka <mamaduka@git.wordpress.org>
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[ntsekouras]

Shouldn't we remove first (or at the same PR) the compat layer for 6.6?

[ockham]

Shouldn't we remove first (or at the same PR) the compat layer for 6.6?

Sure! I see that's what you did for 6.5 (#64096 before #64126). Looks like you also had to remove the 6.4 compat layer in #64096 since I didn't do that in #60780 🙈 So it's probably a good idea to do it at once.

I'll push a commit 👍

[ramonjd]

Thanks @ockham I smoke tested the site editor and the revisions controller stuff in particular. From my perspective LGTM

[Mamaduka]

Smoke-tested editors and everything looks to be working correctly.

No PHP errors or warnings in logs.

[github-actions]

Flaky tests detected in f602432.
Some tests passed with failed attempts. The failures may not be related to this commit but are still reported for visibility. See the documentation for more information.

🔍 Workflow run URL: https://github.com/WordPress/gutenberg/actions/runs/11929986618
📝 Reported issues:

• [Flaky Test] should allow user to add and remove multiple local font files #62862 in /test/e2e/specs/site-editor/font-library.spec.js

[desrosj]

Just a heads up that when we bump minimum version requirements, we do need to make a Core SVN change to pin the last compatible version of the Gutenberg plugin in the E2E test workflow for any branch losing support. I've gone and opened #67167 to add this to the documentation, and Core-62488 to make this change once 19.8 enters RC phase.

[ockham]

TIL 😅 Thank you @desrosj!

[github-actions]

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[ockham]

Just a heads up that when we bump minimum version requirements, we do need to make a Core SVN change to pin the last compatible version of the Gutenberg plugin in the E2E test workflow for any branch losing support. I've gone and opened #67167 to add this to the documentation, and Core-62488 to make this change once 19.8 enters RC phase.

PR here: WordPress/wordpress-develop#8008