Change test to use correct node type

Class name is an Identifier, not a Name.

Author: nikic

test/code/formatPreservation/anonClasses.test

@@ -21,7 +21,7 @@ new class
 -----
 // Ignore name assigned to anon class
 $new = $stmts[0]->expr;
-$new->class->name = new Node\Name('Anon1');
+$new->class->name = new Node\Identifier('Anon1');
 -----
 <?php
 new class