[auth][l10n] Added Ukrainian translation (#2806)

## Description

## Tests

Co-authored-by: stro <stro@cpan.org>

auth/lib/locale.dart

@@ -17,6 +17,7 @@ const List<Locale> appSupportedLocales = <Locale>[
   Locale('pt', 'BR'),
   Locale('ru'),
   Locale('tr'),
+  Locale('uk'),
   Locale("zh", "CN"),
 ];
 

auth/lib/ui/settings/language_picker.dart

@@ -154,6 +154,8 @@ class _ItemsWidgetState extends State<ItemsWidget> {
         return 'Русский';
       case 'tr':
         return 'Türkçe';
+      case 'uk':
+        return 'Українська';
       case 'fi':
         return 'Suomi';
       case 'zh':