Update test_server for conncurrent client auth

This patch updates the test server to have a separate port for
HTTPS with client authentication. This will allow concurrent tests
to run using the HTTPS and HTTPS with client authentication ports.
It adds a new parameter "-https_client_auth_port" for the port that
will require client certificates.

Depends-On: https://review.opendev.org/c/openstack/devstack-gate/+/776722

Change-Id: I6d44787f66904409b7f32a5fe576b658b6eb600a
2 files changed