ipatests: curl outputs the cookie in stderr and not in sdtout
The integration test test_trust.py::TestTrust::test_password_login_as_aduser
is expecting curl to output the cookie obtained after password login
in stdout but should use stderr instead.
Fixes: https://pagure.io/freeipa/issue/8559
Reviewed-By: Alexander Bokovoy <abokovoy@redhat.com>
Reviewed-By: Rob Crittenden <rcritten@redhat.com>