Add test for final readonly classes

Author: kocsismate

Zend/tests/readonly_classes/readonly_class_final_modifier.phpt

@@ -0,0 +1,16 @@
+--TEST--
+The readonly and final class modifiers can be defined in the same time
+--FILE--
+<?php
+
+final readonly class Foo
+{
+}
+
+readonly class Bar extends Foo
+{
+}
+
+?>
+--EXPECTF--
+Fatal error: Class Bar cannot extend final class Foo in %s on line %d