Fix array double arrow alignment in kses tests

WordPress coding standards require aligned double arrows
in multi-line arrays. Adjusts spacing so all arrows in the
data provider align with the longest key.

Author: adamsilverstein

tests/phpunit/tests/kses.php

@@ -2720,11 +2720,11 @@ public function test_wp_kses_srcset_preserves_spacing( $input, $expected ) {
 
 	public function data_wp_kses_srcset_preserves_spacing() {
 		return array(
-			'no space after comma'       => array(
+			'no space after comma'        => array(
 				'image1.jpg 1x,image2.jpg 2x',
 				'image1.jpg 1x,image2.jpg 2x',
 			),
-			'single space after comma'   => array(
+			'single space after comma'    => array(
 				'image1.jpg 1x, image2.jpg 2x',
 				'image1.jpg 1x, image2.jpg 2x',
 			),