Added test class for executing tests without ipa server being
configured. This is achieved by not providing topology attribute in the
test class. Subsequently implemented test for PG6843 - ipa-backup does not create
log file at /var/log/ - by invoking ipa-backup command with ipa server
not configured and checking for expected error code presence of /var/log
in the error message.
https://pagure.io/freeipa/issue/6843
Reviewed-By: Florence Blanc-Renaud <frenaud@redhat.com>
Reviewed-By: Tibor Dudlák <tdudlak@redhat.com>
Reviewed-By: François Cami <fcami@redhat.com>
