Add test for iterable+Traversable redundancy with extra class

Author: nikic

Zend/tests/type_declarations/union_types/redundant_types/iterable_and_Traversable_2.phpt

@@ -0,0 +1,11 @@
+--TEST--
+Using both iterable and Traversable, with extra classes
+--FILE--
+<?php
+
+function test(): iterable|Traversable|ArrayAccess {
+}
+
+?>
+--EXPECTF--
+Fatal error: Type Traversable|ArrayAccess|iterable contains both iterable and Traversable, which is redundant in %s on line %d