changed primary color usage to fix the color bug in dark mode

Changed Theme.of(context).primaryColor to Theme.of(contex).colorScheme.primary to make dark mode work properly.

lib/features/customer_info/screens/customer_info_screen.dart

@@ -19,7 +19,9 @@ class _CustomerInfoScreenState extends State<CustomerInfoScreen> {
     return Scaffold(
       appBar: AppBar(
         title: Text(
-          AppLocalizations.of(context).customerInfo,
+          AppLocalizations.of(context)
+              .customerInfo
+              .replaceFirst(RegExp('\n'), ''),
         ),
       ),
       body: SingleChildScrollView(