Create go-live support tickets using the new way

The new way of creating support tickets can be seen in
[notifications-utils](https://github.com/alphagov/notifications-utils/pull/899).

This changes tickets created when making a request to go live to use
the new way, while other tickets stay the same for now.

The go live tags have been removed. Some of these had become
unneccessary since you can't make the request to go live unless they are
true (e.g. `notify_go_live_email_reply_to`). Others will always get
added by a Zendesk macro when the ticket is replied to, so we don't need
to add them here.

app/models/service.py

@@ -684,33 +684,6 @@ class Service(JSONModel):
             }
         )
 
-    @property
-    def request_to_go_live_tags(self):
-        return list(self._get_request_to_go_live_tags())
-
-    def _get_request_to_go_live_tags(self):
-
-        BASE = 'notify_go_live'
-
-        yield 'notify_action'
-        yield BASE
-
-        if self.go_live_checklist_completed and self.organisation.agreement_signed:
-            yield BASE + '_complete'
-            return
-
-        for test, tag in (
-            (not self.volumes, '_volumes'),
-            (not self.go_live_checklist_completed, '_checklist'),
-            (not self.organisation.agreement_signed, '_mou'),
-            (self.needs_to_add_email_reply_to_address, '_email_reply_to'),
-            (not self.has_team_members, '_team_member'),
-            (not self.has_templates, '_template_content'),
-            (self.needs_to_change_sms_sender, '_sms_sender'),
-        ):
-            if test:
-                yield BASE + '_incomplete' + tag
-
     @cached_property
     def returned_letter_statistics(self):
         return service_api_client.get_returned_letter_statistics(self.id)