Support for identity section in tempest.conf was deprecated 7 years ago by the refstack-client [1]. This patch simply makes sure that the refstack-client ends with an error and prints an error message when the user tries to use identity section instead of accounts.yaml. [1] https://review.opendev.org/c/openinfra/refstack-client/+/287540 Change-Id: I9e6cce47ffd4269fecdb3ad040d508acb1be671c