improve report

enrollments-events/tests/events/reporting/test_append_cert.py

@@ -39,9 +39,9 @@ def test_append_cert(
     assert app.lambda_handler(event, lambda_context)  # type: ignore
 
     # The reporting month is the month before the certificate expires
-    month_start = (cert_expires_at.replace(day=1) - timedelta(days=1)).replace(day=1)
+    report_month = (cert_expires_at.replace(day=1) - timedelta(days=1)).replace(day=1)
     report_sk = 'MONTH#{}#SCHEDULE#SEND_REPORT_EMAIL'.format(
-        month_start.strftime('%Y-%m')
+        report_month.strftime('%Y-%m')
     )
 
     r = dynamodb_persistence_layer.collection.get_items(