Paginate search results for notifications

The standard way that we indicate that there are more results than can
be returned is by paginating. So even though we don’t intend to paginate
the search results in the admin app, it can still use the presence or
absence of a ‘next’ link to determine whether or not to show a message
about only showing the first 50 results.

app/dao/notifications_dao.py

@@ -586,7 +586,14 @@ def dao_update_notifications_by_reference(references, update_dict):
 
 
 @statsd(namespace="dao")
-def dao_get_notifications_by_recipient_or_reference(service_id, search_term, notification_type=None, statuses=None):
+def dao_get_notifications_by_recipient_or_reference(
+    service_id,
+    search_term,
+    notification_type=None,
+    statuses=None,
+    page=1,
+    page_size=None,
+):
 
     if notification_type == SMS_TYPE:
         normalised = try_validate_and_format_phone_number(search_term)
@@ -636,8 +643,7 @@ def dao_get_notifications_by_recipient_or_reference(service_id, search_term, not
     results = db.session.query(Notification)\
         .filter(*filters)\
         .order_by(desc(Notification.created_at))\
-        .limit(current_app.config['PAGE_SIZE'])\
-        .all()
+        .paginate(page=page, per_page=page_size)
     return results