Declare orderby_hierarchy in post controller test

Author: oandregal

src/wp-includes/rest-api/endpoints/class-wp-rest-posts-controller.php

@@ -3007,8 +3007,10 @@ public function get_collection_params() {
 				),
 				'default'     => array(),
 			);
+		}
+		if ( $post_type->hierarchical ) {
 			$query_params['orderby_hierarchy'] = array(
-				'description' => 'Sort pages by hierarchy.',
+				'description' => __( 'Whether the post should be grouped by parent-child relationship (hierarchy).' ),
 				'type'        => 'boolean',
 				'default'     => false,
 			);

tests/phpunit/tests/rest-api/rest-posts-controller.php

@@ -203,6 +203,7 @@ public function test_registered_query_params() {
 				'offset',
 				'order',
 				'orderby',
+				'orderby_hierarchy',
 				'page',
 				'per_page',
 				'search',