celery test cleanup

* Alter config so an error will be raised if you forget to mock out a
  celery call in one of your tests
* Remove an unneeded exception type that was masking errors

app/notifications/__init__.py

@@ -1,7 +0,0 @@
-
-
-class SendNotificationToQueueError(Exception):
-    status_code = 500
-
-    def __init__(self):
-        self.message = "Failed to create the notification"

app/notifications/process_notifications.py

@@ -17,7 +17,7 @@ from app.models import SMS_TYPE, Notification, KEY_TYPE_TEST, EMAIL_TYPE, Schedu
 from app.dao.notifications_dao import (dao_create_notification,
                                        dao_delete_notifications_and_history_by_id,
                                        dao_created_scheduled_notification)
-from app.v2.errors import BadRequestError, SendNotificationToQueueError
+from app.v2.errors import BadRequestError
 from app.utils import get_template_instance, cache_key_for_service_template_counter, convert_bst_to_utc
 
 
@@ -110,10 +110,9 @@ def send_notification_to_queue(notification, research_mode, queue=None):
 
     try:
         deliver_task.apply_async([str(notification.id)], queue=queue)
-    except Exception as e:
-        current_app.logger.exception(e)
+    except Exception:
         dao_delete_notifications_and_history_by_id(notification.id)
-        raise SendNotificationToQueueError()
+        raise
 
     current_app.logger.info(
         "{} {} sent to the {} queue for delivery".format(notification.notification_type,