Bug 21865: allow test arg alone

Signed-off-by: Bernardo Gonzalez Kriegel <bgkriegel@gmail.com>
Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>
Signed-off-by: Martin Renvoize <martin.renvoize@ptfs-europe.com>

Signed-off-by: Joy Nelson <joy@bywatersolutions.com>
(cherry picked from commit 8523817dcc)

Signed-off-by: Lucas Gass <lucas@bywatersolutions.com>

misc/migration_tools/remove_unused_authorities.pl

@@ -38,7 +38,7 @@ GetOptions(
     'h|help'             => \$want_help,
 );
 
-if ( $want_help || !$confirm ) {
+if ( $want_help || !($test || $confirm) ) {
     print_usage();
     exit 0;
 }