[ticket/13061] Replace the service event.subscriber_loader by a compiler pass

https://tracker.phpbb.com/browse/PHPBB3-13061
https://tracker.phpbb.com/browse/PHPBB3-12653

I also replaced \phpbb\di\kernel_pass by the generic RegisterListenersPass provided by the HttpKernel Component.

PHPBB3-13061
PHPBB3-12653