tests: remove LOCAL_SYSDB_FILE reference from common_dom
As all tests are now taking advantage of the "files" provider instead of
the "local" one, let's just remove the last reference of
LOCAL_SYSDB_FILE from our tests.
Together with the reference, let's also remove the whole if-block as
we're not relying on "local" provider anymore.
Related:
https://pagure.io/SSSD/sssd/issue/3304
Signed-off-by: Fabiano Fidêncio <fidencio@redhat.com>
Reviewed-by: Jakub Hrozek <jhrozek@redhat.com>
Reviewed-by: Pavel Březina <pbrezina@redhat.com>