[ticket/12918] Load class fileupload in fileupload_remote_test.php.

PHPBB3-12918
Merge pull request #2811 from bantu/ticket/12918

[ticket/12918] Load class fileupload in fileupload_remote_test.php.

* bantu/ticket/12918:
  [ticket/12918] Load class fileupload in fileupload_remote_test.php.