Bug 16187: (QA follow-up) Additional fixes

Bug 16187: (QA follow-up) Additional fixes

Fix:
Can't locate object method "next" via package "13" (perhaps you forgot to load "13"?) at misc/cronjobs/holds/cancel_unfilled_holds.pl line 119.
Undefined subroutine &main::CancelReserve called at misc/cronjobs/holds/cancel_unfilled_holds.pl line 143.

The script does not use Koha::Object's get_column correctly for getting
the branch codes.
The call to CancelReserve is obsolete. Was moved in the meantime to
Koha::Hold->cancel.

Signed-off-by: Marcel de Rooy <m.de.rooy@rijksmuseum.nl>
Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>