Allow new role 'regress_dump_login_role' to log in under SSPI.

Semi-blind attempt to fix a70f2a57f to work on Windows,
along the same lines as 5253519b2.  Per buildfarm.

src/test/modules/test_pg_dump/t/001_base.pl

@@ -776,7 +776,7 @@ my %tests = (
 # Create a PG instance to test actually dumping from
 
 my $node = PostgreSQL::Test::Cluster->new('main');
-$node->init;
+$node->init('auth_extra' => [ '--create-role', 'regress_dump_login_role' ]);
 $node->start;
 
 my $port = $node->port;