Pass valid ticket type to Zendesk

The feedback endpoints use `ticket_type` to decide what to display and
whether or not a ticket should be escalated. We were using the
ticket_type as the value for the Zendesk ticket_type. However, the Zendesk
API accepts 4 values for its ticket_type and these are different from
the ticket_type values we use in our code.

This change converts the Notify ticket_type value to a valid Zendesk
ticket_type value when creating a Notify feedback ticket.

app/main/views/feedback.py

@@ -130,7 +130,7 @@ def feedback(ticket_type):
         ticket = NotifySupportTicket(
             subject='Notify feedback',
             message=feedback_msg,
-            ticket_type=ticket_type,
+            ticket_type=get_zendesk_ticket_type(ticket_type),
             p1=out_of_hours_emergency,
             user_name=user_name,
             user_email=user_email,
@@ -231,3 +231,14 @@ def needs_escalation(ticket_type, severe):
         not current_user.is_authenticated,
         not in_business_hours(),
     ))
+
+
+def get_zendesk_ticket_type(ticket_type):
+    # Zendesk has 4 ticket types - "problem", "incident", "task" and "question".
+    # We don't want to use a Zendesk "problem" ticket type when someone reports a
+    # Notify problem because they are designed to group multiple incident tickets together,
+    # allowing them to be solved as a group.
+    if ticket_type == PROBLEM_TICKET_TYPE:
+        return NotifySupportTicket.TYPE_INCIDENT
+
+    return NotifySupportTicket.TYPE_QUESTION