Remove unnecessary include of BoardsHelper

I was mislead into this being needed during my testing as `BoardsHelper`
didn't seem to be available within the view but it seemed to be because
there was no `helpers` directory initially so it wasn't going to be autoloaded
until I stopped spring and restarted the rails server.

This is indeed unnecessary; Thanks Oliver.

modules/boards/app/controllers/boards/boards_controller.rb

@@ -1,7 +1,5 @@
 module ::Boards
   class BoardsController < BaseController
-    include ::BoardsHelper
-
     before_action :find_optional_project
     before_action :build_board_grid, only: %i[new]