fix(core): Omit saving Order.customFields on applyPriceAdjustments

This change prevents accidental loss of data due to race
conditions where multiple parallel code paths attempt
to modify a particular order, where one path involves
setting a custom field value and another path involves
changing the contents of the order in a way that would
trigger a re-calculation of order totals.

packages/core/src/service/services/order.service.ts

@@ -2124,6 +2124,7 @@ export class OrderService {
                     'sellerOrders',
                     'customer',
                     'modifications',
+                    'customFields',
                 ]),
                 {
                     reload: false,