[ticket/11405] Move test to submit_post_base.php and use data sets for testing

PHPBB3-11405
[ticket/11405] Add unit tests for bookmarking

PHPBB3-11405
[ticket/11405] Use different fixtures so it's not a total mess

PHPBB3-11405
[ticket/11405] Order users in bookmark, in order to pass postgres tests

PHPBB3-11405
[ticket/11405] Add unit tests for post_in_queue

PHPBB3-11405
[ticket/11474] Remove invalid forum_id fallback code

The forum_id of a topic/post can not be 0 anymore

PHPBB3-11474
PHPBB3-11405
[ticket/11474] Check forum read permissions before sending notifications

PHPBB3-11474
PHPBB3-11405