Add setting to disable layout content and wide size controls.

[tellthemachines]

Trac ticket: https://core.trac.wordpress.org/ticket/60133

Syncs the PHP changes from WordPress/gutenberg#56236. Similar to #5147, this can't be tested without the JS changes from the npm package updates.

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[github-actions]

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[andrewserong]

This change looks safe to land to me, given that it's only adding another valid setting and that setting has been working nicely in the Gutenberg plugin for a couple of cycles.

LGTM!

[tellthemachines]

Committed in r57247.