Bug 18179: Update existing calls

Bug 18179: Update existing calls

This patch updates the existing occurrences of ->find called in a list
context.
There are certainly others that are not easy to catch with git grep.
Test plan:
Confirm that the 4 modified scripts still works as expected.

We need this one ASAP in master to make sure we will not get other
side-effects of this kind and to catch possible uncaught occurrences
before the release.

Tested scripts changed by this patch, they work as expected.
Signed-off-by: Marc Véron <veron@veron.ch>
Signed-off-by: Nick Clemens <nick@bywatersolutions.com>
Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>