Fix rally deployment check fails with https auth_url

When create keystone client, rally will add admin_port(35357) to
auth_url if auth_url doesn't contain an obvious port. And thus,
causing the change of https auth_url.

So we should ignore adding admin_port for https auth_url.

Change-Id: If518687839c5e0734b85b69c680f7d124e135e94
Closes-bug: #1397160