ui_tests: add more test cases to test_certification
    
    Add cases for:
    "cancel_cert_request", "cancel_hold_cert", "cancel_remove_hold",
    "cancel_revoke_cert" and "revoke_cert"
    
    https://pagure.io/freeipa/issue/7441
    
    Reviewed-By: Petr Vobornik <pvoborni@redhat.com>