Block editor Yoast panel: remove if/else and refactor to use selector [after dropping WP 6.4 support]

[enricobattocchi]

We have had a patch release for Gutenberg preferences that moved from edit-post to editor.
After this move of selectors and actions, we ran into it and fixed it (unfortunately, first only for 21.9, then patch for 21.8).
They detected this and fixed it too, resulting in a PR that deprecates the selector we use.

It was mentioned that they expect us to use the isEditorPanelOpened selector instead of using the preferences directly. So let's do that. But only after we no longer need to support edit-post, then we can remove the if/else and refactor in one go. When can we then pick up this issue? The edit-post version is included in WP 6.4 (and Gutenberg 17.3). So I think that means whenever we drop support for WP 6.4

Sources

Gutenberg

• Original PR on Gutenberg: Editor: Migrate and unify the panel preferences WordPress/gutenberg#57529
• Discussion on prototype fix PR on Gutenberg: (edit-post)(preferences)(workaround) Keep openPanels and inactivePanels preferences in the core/edit-post` scope to satisfy existing consumers WordPress/gutenberg#57988
  • Merged PR on Gutenberg: Preferences: Add a proxy to retrieve the deprecated preferences with a deprecation message WordPress/gutenberg#58016

WordPress SEO (free)

• Original issue on Free: Gutenberg: Uncaught TypeError: Cannot read properties of undefined (reading 'includes') #21021
• Patch: https://github.com/Yoast/wordpress-seo/releases/tag/21.8.1
  • Original 2 PRs that were targeting 21.9 (they got cherry-picked into the above patch later):
    • Gutenberg 17.5: Fix the opening of our document panel in WP 6.5 #21024
    • Gutenberg 17.4.1: Fix the opening of our document panel in Gutenberg 17.4.1 #21030