Synonyms: ignore ep-synonym post status

[felipeelia]

Description of the Change

This PR changes the WP_Query to fetch ep-synonyms, getting all synonyms with any post status. It also makes the check a little looser, simply checking it the post count is greater than or equal to 1, in case someone is changing posts_per_page in all queries.

Applicable Issues

Closes #2516

Changelog Entry

Fixed: Synonyms erased when syncing via WP-CLI. Props @felipeelia and @oscarssanchez

[felipeelia]

Users facing this problem can fix it by adding the following snippet to a custom plugin or their theme's functions.php:

add_action(
	'pre_get_posts',
	function ( $query ) {
		$post_type = (array) $query->get( 'post_type', [] );
		if ( in_array( 'ep-synonym', $post_type, true ) ) {
			$query->set( 'post_status', 'any' );
		}
	}
);

[felipeelia]

The following snippet can be used to delete all synonyms created by that bug and bring back the last edited synonyms list. It can be used by adding it to the codebase, opening any page, and then erasing it (it only needs to be executed once.)

add_action(
	'init',
	function() {
		global $wpdb;

		$synonyms = \ElasticPress\Features::factory()->get_registered_feature( 'search' )->synonyms;

		$synonyms_example_ids = $wpdb->get_col(
			$wpdb->prepare(
				"SELECT ID FROM {$wpdb->posts} WHERE post_type = %s AND post_content = %s LIMIT 500",
				$synonyms::POST_TYPE_NAME,
				$synonyms->example_synonym_list()
			)
		);

		if ( ! $synonyms_example_ids ) {
			return;
		}

		foreach ( $synonyms_example_ids as $synonym_post_id ) {
			wp_delete_post( $synonym_post_id, true );
		}
	}
);