How come drongo didn't fail authentication here?

In commits 7c34555f8/e1bd4990b, I added a new role used by a TAP
script but neglected the auth_extra incantation needed to allow
login as that role.  This should have resulted in SSPI auth
failures on certain Windows configurations, and indeed it did
on drongo's next run in the v15 branch:

https://buildfarm.postgresql.org/cgi-bin/show_log.pl?nm=drongo&dt=2022-07-27%2022%3A01%3A47

However, its immediately-following run on HEAD succeeded,
though I'd obviously not had time to put in the fix yet:

https://buildfarm.postgresql.org/cgi-bin/show_log.pl?nm=drongo&dt=2022-07-27%2022%3A30%3A27

How can that be?  Have we somehow broken SSPI authentication
in HEAD?

            regards, tom lane