[ticket/13338] Move insert_config_array_test to functions_acp, add deps.

PHPBB3-13338
[ticket/13338] Do not use the _test.php suffix for abstract test case classes.

PHPBB3-13338
[ticket/13338] Add include statements for dependencies.

PHPBB3-13338
Merge pull request #3145 from bantu/ticket/13338

[ticket/13338] Make all tests run on their own. Avoid _test suffix for abstract test case classes.