Bug 9239 QA follow-up: amend error handling

Signed-off-by: Katrin Fischer <Katrin.Fischer.83@web.de>
Signed-off-by: Jared Camins-Esakov <jcamins@cpbibliography.com>

C4/AuthoritiesMarc.pm

@@ -1213,8 +1213,8 @@ sub GetAuthorizedHeading {
     unless ($record = $args->{record}) {
         return unless $args->{authid};
         $record = GetAuthority($args->{authid});
-        return unless $record;
     }
+    return unless (ref $record eq 'MARC::Record');
     if (C4::Context->preference('marcflavour') eq 'UNIMARC') {
 # construct UNIMARC summary, that is quite different from MARC21 one
 # accepted form