Delete spree_user_signup which is from spree promotions code that we dont use

app/controllers/spree/user_registrations_controller.rb

@@ -23,7 +23,6 @@ module Spree
       if resource.save
         set_flash_message(:notice, :signed_up)
         sign_in(:spree_user, @user)
-        session[:spree_user_signup] = true
         associate_user
         respond_with resource, location: after_sign_up_path_for(resource)
       else

app/controllers/user_registrations_controller.rb

@@ -16,7 +16,6 @@ class UserRegistrationsController < Spree::UserRegistrationsController
       return render_error(@user.errors)
     end
 
-    session[:spree_user_signup] = true
     session[:confirmation_return_url] = params[:return_url]
     associate_user
 

lib/spree/core/controller_helpers/order.rb

@@ -65,15 +65,6 @@ module Spree
             end
           end
 
-          # This will trigger any "first order" promotions to be triggered
-          # Assuming of course that this session variable was set correctly in
-          # the authentication provider's registrations controller
-          if session[:spree_user_signup] && @order
-            fire_event('spree.user.signup', user: spree_current_user,
-                                            order: @order)
-            session[:spree_user_signup] = nil
-          end
-
           session[:guest_token] = nil
         end