Add ability to restrict by post status

[renatonascalves]

Description

See here, alleyinteractive/archiveless#62, a scenario where this functionality can be useful.

add_action(
	'elasticsearch_extensions_config',
	 function( $es_config ) {
		$es_config
			->restrict_post_statuses( [ 'publish', 'my-custom-status' ] )
			->enable_taxonomy_aggregation( 'category' )
			->enable_taxonomy_aggregation( 'post_tag' );
	 }
);

VIP Search has a hook that it uses to confirm if a post should be indexed or not. This plugin can make use of this hook.

Use Case

See this issue for a use case.