ipatests: remove invalid parameter from sssd.conf

`use_fully_qualified_names` is not a valid parameter for `[sssd]` section
of sssd.conf, it can be specified only in domain section.
According to `man sssd.conf` it simply requires all requests to be fully
qualified, otherwise no result will be found. It is irrelevant to the
test scenario, so removing it.

Related to: https://pagure.io/freeipa/issue/8219

Reviewed-By: Alexander Bokovoy <abokovoy@redhat.com>

ipatests/test_integration/test_sssd.py

@@ -164,8 +164,6 @@ class TestSSSDWithAdTrust(IntegrationTest):
         for host in hosts:
             with tasks.remote_sssd_config(host) as sssd_conf:
                 sssd_conf.edit_service('sssd', 're_expression', expression)
-                sssd_conf.edit_service(
-                    'sssd', 'use_fully_qualified_names', True)
             tasks.clear_sssd_cache(host)
         try:
             cmd = ['getent', 'group', ad_group]