Merge remote-tracking branch 'bantu/ticket/11439' into develop

* bantu/ticket/11439:
  [ticket/11439] Add _test suffix to notification test filename.
[ticket/11441] Add _test suffix to user loader test filename.

PHPBB3-11441
[ticket/11441] Correct/fix class name of user loader test.

PHPBB3-11441
[ticket/11441] Update/correct copyright year of user loader test.

PHPBB3-11441
[ticket/11441] Use setUp() in phpbb_user_loader_test.

PHPBB3-11441
[ticket/11441] Split user loader tests into multiple test methods.

PHPBB3-11441