pytest: sid_strings: adjust to match Windows 2016

pytest: sid_strings: adjust to match Windows 2016

9 hex-digit subauths like '0xABCDef123' will not fit in 32 bits, so
should be rejected on parsing.

In other situations, such as defaultSecurityDescriptor, overflowing
SID subauths on Windows will saturate to 0xffffffff, resulting in a
valid but probably meaningless SID. It is possible that in previous
testing we saw that here, but it is more likely I got confused. In any
case, now I see them being rejected, and that is good.

The saturating defaultSecurityDescriptor case is tested in
SidStringBehavioursThatWindowsAllows.

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>