[feature/auth-refactor] Move test classes into separate directory

PHPBB3-9734

tests/acp_board/auth_provider/invalid.php

@@ -0,0 +1,13 @@
+<?php
+/**
+*
+* @package testing
+* @copyright (c) 2013 phpBB Group
+* @license http://opensource.org/licenses/gpl-2.0.php GNU General Public License v2
+*
+*/
+
+class phpbb_auth_provider_acp_board_invalid
+{
+
+}