Added comma on the last array item

Author: shazzad

src/wp-admin/includes/update-core.php

@@ -847,7 +847,7 @@
 	'wp-includes/blocks/post-author/editor-rtl.css',
 	'wp-includes/blocks/post-author/editor-rtl.min.css',
 	'wp-includes/SimplePie/src/Decode',
-	'wp-includes/SimplePie/src/Core.php'
+	'wp-includes/SimplePie/src/Core.php',
 );
 
 /**