delete unused ticket id

lib/pages/ticket_page.dart

@@ -42,12 +42,9 @@ class TicketPage extends StatefulWidget {
 
 class _TicketPageState extends State<TicketPage> {
   static const _ticketNameMap = {
-    1: '功能票',
     2: '2倍功能票',
-    3: '3倍功能票',
     4: '4倍功能票',
-    5: '5倍功能票',
-    6: '6倍功能票',
+    5: '5倍功能票'
   };
 
   TicketStep _step = TicketStep.idle;