remove reply_to_addresses from task kwargs

also added a test for aws_ses.send_email to prove it handles reply_to_address correctly

tests/app/clients/test_aws_ses.py

@@ -1,5 +1,7 @@
 import pytest
+from unittest.mock import Mock, ANY
 
+from app import aws_ses_client
 from app.clients.email.aws_ses import get_aws_responses
 
 
@@ -39,3 +41,29 @@ def test_should_be_none_if_unrecognised_status_code():
     with pytest.raises(KeyError) as e:
         get_aws_responses('99')
     assert '99' in str(e.value)
+
+
+@pytest.mark.parametrize(
+    'reply_to_address, expected_value',
+    [(None, []), ('foo@bar.com', ['foo@bar.com'])],
+    ids=['empty', 'single_email']
+)
+def test_send_email_handles_reply_to_address(notify_api, mocker, reply_to_address, expected_value):
+    boto_mock = mocker.patch.object(aws_ses_client, '_client', create=True)
+    mocker.patch.object(aws_ses_client, 'statsd_client', create=True)
+
+    with notify_api.app_context():
+        aws_ses_client.send_email(
+            Mock(),
+            Mock(),
+            Mock(),
+            Mock(),
+            reply_to_address=reply_to_address
+        )
+
+    boto_mock.send_email.assert_called_once_with(
+        Source=ANY,
+        Destination=ANY,
+        Message=ANY,
+        ReplyToAddresses=expected_value
+    )