pytest: sid_strings: use more reliable well known SID

pytest: sid_strings: use more reliable well known SID

It seems as if the well-known SID S-1-5-32-579
(DOMAIN_ALIAS_RID_ACCESS_CONTROL_ASSISTANCE_OPS) is
not always present -- specifically, it was not there on the
Windows machine used to develop these tests, but it is there on
the one I am now using.

S-1-5-32-545 (DOMAIN_ALIAS_RID_USERS) is surely going to exist,
so we use that instead.

That changes some of the assertions, making some NO_SUCH_OBJECTs
into successes.

For these tests we are only interested in the parsing of the SIDs, not
their meaning, so it's OK to change it.

BUG: https://bugzilla.samba.org/show_bug.cgi?id=10763

Signed-off-by: Douglas Bagnall <douglas.bagnall@catalyst.net.nz>
Reviewed-by: Andrew Bartlett <abartlet@samba.org>