Remove the briton kennel as it's not historically correct.
War dogs are limited to a total of 20 instead of a five kennels times ten dogs each, to compensate for the fact they no longer have special requirements.

Patch by: @Nescio
Reviewed by: @borg-, @Stan

Thread: https://wildfiregames.com/forum/index.php?/topic/25620-kennel-issues/&tab=comments#comment-372159

Differential Revision: https://code.wildfiregames.com/D2533