What?

Related #68680.

PR fixes the return value of isEditedPostAutosaveable selector when a post type doesn't support autosave.

Why?

The selector is used by AutosaveMonitor and was providing it with a false value.

Testing Instructions

1. Disable autosaves for posts.
2. Create a post and add some content.
3. Using DevTools, check if the edited post is autosavable - wp.data.select( 'core/editor' ).isEditedPostAutosaveable()
4. Selector should return a value based on the post type support flag.

// Disable autosave for posts.
add_action( 'init', function() {
	remove_post_type_support( 'post', 'autosave' );
} );

Testing Instructions for Keyboard

Same.