change page navigation

lib/pages/invoice/box_addition.dart

@@ -3,6 +3,7 @@ import 'package:fcs/helpers/theme.dart';
 import 'package:fcs/localization/app_translations.dart';
 import 'package:fcs/pages/box/model/box_model.dart';
 import 'package:fcs/pages/widgets/progress.dart';
+import 'package:flutter/cupertino.dart';
 import 'package:flutter/material.dart';
 import 'package:provider/provider.dart';
 
@@ -40,7 +41,7 @@ class _BoxAdditionState extends State<BoxAddition> {
         appBar: AppBar(
           centerTitle: true,
           leading: new IconButton(
-            icon: new Icon(Icons.close),
+            icon: new Icon(CupertinoIcons.back),
             onPressed: () => Navigator.of(context).pop(),
           ),
           backgroundColor: primaryColor,