Bug 29523: (QA follow-up) Catch remaining SUPER::to_api cases

Bug 29523: (QA follow-up) Catch remaining SUPER::to_api cases

Koha::Object->to_api can now return undefined.. we should be catching
that cases in all post manipulation cases.

Signed-off-by: Martin Renvoize <martin.renvoize@ptfs-europe.com>
Signed-off-by: Tomas Cohen Arazi <tomascohen@theke.io>
Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>
Signed-off-by: Marcel de Rooy <m.de.rooy@rijksmuseum.nl>
Signed-off-by: Tomas Cohen Arazi <tomascohen@theke.io>