Make bill rollback if git merge fails (#302)

Author: mfosterw

democrasite/webiscite/tasks.py

@@ -11,6 +11,7 @@
 from celery import shared_task
 from celery.utils.log import get_task_logger
 from django.conf import settings
+from django.db import transaction
 from github import Auth
 from github import Github
 from github.Repository import Repository
@@ -22,6 +23,7 @@
 
 
 @shared_task
+@transaction.atomic
 def submit_bill(bill_id: int) -> None:
     """Handles the final processing and closing of a bill