[backend] Documents : correction bug total produits

common/models/Document.php

         public function getProductsOrders()
         {
                 $productsOrdersArray = [];
-                if ($this->orders && count($this->orders)) {
-                        foreach ($this->orders as $order) {
+                $ordersArray = $this->orders ;
+                if ($ordersArray && count($ordersArray)) {
+                        foreach ($ordersArray as $order) {
                                 foreach ($order->productOrder as $productOrder) {
                                         if (!isset($productsOrdersArray[$productOrder->id_product])) {
-                                                $productsOrdersArray[$productOrder->id_product] = [$productOrder];
+                                                $newProductOrder = clone $productOrder ;
+                                                $productsOrdersArray[$productOrder->id_product] = [$newProductOrder];
                                         } else {
                                                 $productOrderMatch = false;
                                                 foreach ($productsOrdersArray[$productOrder->id_product] as &$theProductOrder) {