fix for Mojo::UserAgent usage

bin/update-metadata

@@ -76,7 +76,7 @@ foreach my $id (keys %{$configuration->{federations}}) {
 
     if (!$result->is_success()) {
         $db->rollback();
-        die "failed to download federation metadata: " . $result->status_line();
+        die "failed to download federation metadata: " . $result->message();
     }
 
     $result->save_to($file->filename());