test(iam): pin functional login tests to the zero-UUID default client

gcl_iam>=1.3.0 changed GenesisCoreAuth's default client_uuid from the
zero-UUID to the "default" alias, which only resolves through an LB in
front of the IAM client. These functional tests run the app in-process
with no LB, so pass client_uuid explicitly to keep using the seeded
zero-UUID default client.

Author: gmelikov

exordos_core/tests/functional/restapi/iam/test_users.py

@@ -683,6 +683,7 @@ def test_auth_with_param(
             "username": None,
             "password": auth_test1_user.password,
             "grant_type": grant_type,
+            "client_uuid": common_c.DEFAULT_CLIENT_UUID,
         }
         params[auth_param] = (getattr(auth_test1_user, auth_param, None),)
         auth = iam_clients.GenesisCoreAuth(**params)
@@ -717,6 +718,7 @@ def test_auth_with_login(
             "password": auth_test1_user.password,
             "grant_type": iam_c.GRANT_TYPE_PASSWORD_LOGIN,
             "login": getattr(auth_test1_user, login, "doesnt_exist"),
+            "client_uuid": common_c.DEFAULT_CLIENT_UUID,
         }
         if password is not None:
             params["password"] = password
@@ -755,6 +757,7 @@ def test_auth_case_insensitivity(
             "username": None,
             "password": auth_test1_user.password,
             "grant_type": grant_type,
+            "client_uuid": common_c.DEFAULT_CLIENT_UUID,
         }
         params[field_name] = login