Remove separate function for live service check

When we get a support ticket we need to check whether a user has any
live services.

We have a method for this on the user model now, so we don’t need a
separate function in the feedback code.

It wasn’t very well tested so I’ve adapted the old tests from the
feedback view to work against the method on the user model too.

app/main/views/feedback.py

@@ -5,7 +5,7 @@ from flask import redirect, render_template, request, session, url_for
 from flask_login import current_user
 from govuk_bank_holidays.bank_holidays import BankHolidays
 
-from app import convert_to_boolean, current_service, service_api_client
+from app import convert_to_boolean, current_service
 from app.extensions import zendesk_client
 from app.main import main
 from app.main.forms import (
@@ -205,19 +205,12 @@ def is_bank_holiday(time):
     return bank_holidays.is_holiday(time.date())
 
 
-def has_live_services(user_id):
-    return any(
-        service['restricted'] is False
-        for service in service_api_client.get_services({'user_id': user_id})['data']
-    )
-
-
 def needs_triage(ticket_type, severe):
     return all((
         ticket_type != QUESTION_TICKET_TYPE,
         severe is None,
         (
-            not current_user.is_authenticated or has_live_services(current_user.id)
+            not current_user.is_authenticated or current_user.live_services
         ),
         not in_business_hours(),
     ))