Refactor Order::Updater#update so we don't call update_totals twice

Calling this method twice on every update is really expensive and not necessary.

engines/order_management/app/services/order_management/order/updater.rb

@@ -19,6 +19,7 @@ module OrderManagement
       # object with callbacks (otherwise you will end up in an infinite recursion as the
       # associations try to save and then in turn try to call +update!+ again.)
       def update
+        update_all_adjustments
         update_totals
 
         if order.completed?
@@ -27,9 +28,6 @@ module OrderManagement
           update_shipment_state
         end
 
-        update_all_adjustments
-        # update totals a second time in case updated adjustments have an effect on the total
-        update_totals
         persist_totals
       end
 

engines/order_management/spec/services/order_management/order/updater_spec.rb

@@ -132,8 +132,8 @@ module OrderManagement
         end
       end
 
-      it "updates totals twice" do
-        expect(updater).to receive(:update_totals).twice
+      it "updates totals once" do
+        expect(updater).to receive(:update_totals).once
         updater.update
       end