cleanup code

lib/pages/invoice/invoice_table.dart

@@ -4,7 +4,6 @@ import 'package:fcs/domain/entities/invoice.dart';
 import 'package:fcs/domain/entities/rate.dart';
 import 'package:fcs/pages/main/util.dart';
 import 'package:fcs/pages/widgets/local_text.dart';
-import 'package:flutter/cupertino.dart';
 import 'package:flutter/material.dart';
 import 'package:intl/intl.dart';
 
@@ -89,7 +88,7 @@ class InvoiceTable extends StatelessWidget {
     });
     // // add delivery fee
     tableRows.add(InvoiceTableRow(
-        data: invoice!.deliveryFee == null || invoice!.deliveryFee == 0
+        data:  invoice!.deliveryFee == 0
             ? null
             : invoice!.deliveryFee,
         invoiceDataType: InvoiceDataType.DeliveryFeeType,