CVE-2022-38023 selftest:Samba4: avoid global 'allow nt4 crypto = yes' and 'reject...

CVE-2022-38023 selftest:Samba4: avoid global 'allow nt4 crypto = yes' and 'reject md5 clients = no'

Instead of using the generic deprecated option use the specific
allow nt4 crypto:COMPUTERACCOUNT = yes and
server reject md5 schannel:COMPUTERACCOUNT = no
in order to allow legacy tests for pass.

BUG: https://bugzilla.samba.org/show_bug.cgi?id=15240

Signed-off-by: Stefan Metzmacher <metze@samba.org>
Reviewed-by: Andrew Bartlett <abartlet@samba.org>
Reviewed-by: Ralph Boehme <slow@samba.org>
(backported from commit 7ae3735810c2db32fa50f309f8af3c76ffa29768)