fix php unit test

Author: youknowriad

phpunit/class-gutenberg-rest-global-styles-controller-test.php

@@ -110,6 +110,7 @@ public function test_get_theme_items() {
 						),
 					),
 				),
+				'name'     => 'variation',
 			),
 		);
 		$this->assertSameSetsWithIndex( $data, $expected );