Bug 31183: Use filter_by_current in Koha::Holds->get_items_that_can_fill

Bug 31183: Use filter_by_current in Koha::Holds->get_items_that_can_fill

This patch makes the method use the new
Koha::Item::Transfers->filter_by_current one.

To test:
1. Run:
   $ kshell
  k$ prove t/db_dependent/Koha/Holds.t
=> SUCCESS: Tests pass
2. Apply this patch
3. Repeat 1
=> SUCCESS: Tests still pass
4. Sign off :-D

Signed-off-by: Tomas Cohen Arazi <tomascohen@theke.io>
Signed-off-by: Michal Urban <michalurban177@gmail.com>
Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>
Signed-off-by: Tomas Cohen Arazi <tomascohen@theke.io>