Fix plan sorting to use ascending order by rank

Co-authored-by: sorah <[email protected]>

Author: Copilot

app/controllers/admin/conferences_controller.rb

@@ -13,7 +13,7 @@ def show
       .group(:id)
       .select('plans.*, COUNT(sponsorships.plan_id) as cnt')
       .map {|_| [_, _.cnt, _.capacity] }
-      .sort_by { |plan, _cnt, _capa| -plan.rank }
+      .sort_by { |plan, _cnt, _capa| plan.rank }
   end
 
   def attendees_keeper