Try passing in the region in a different place

postgres/tests/test_manage_users.py

@@ -78,7 +78,7 @@ def test_create_or_update_db_user_when_user_exists(self):
 
     @mock_aws
     def test_create_or_update_user_secret(self):
-        ssm = boto3.client("ssm")
+        ssm = boto3.client("ssm", region_name="eu-west-2")
         user_secret_name = "/test/secret"
         user_secret_string = {"username": "test_user", "password": "test_password"}
 
@@ -114,7 +114,7 @@ def test_create_or_update_user_secret_overwrites(self):
     @patch("postgres.manage_users.psycopg2.connect")
     @mock_aws
     def test_handler(self, mock_connect, mock_create_or_update_db_user):
-        secretsmanager = boto3.client("secretsmanager", region_name="eu-west-2")
+        secretsmanager = boto3.client("secretsmanager")
         secret_id = secretsmanager.create_secret(
             Name=self.secret_name, SecretString=self.secret_string
         )["ARN"]