Bug 33971: Remove x-koha-query handing in Orders.pm

Bug 33971: Remove x-koha-query handing in Orders.pm

This patch removes manual handling of `x-koha-query` in the
Orders:list() controller.

There are no tests for the feature but you can verify no behavior is
changed by doing:

1. Run:
   $ ktd --shell
  k$ prove t/db_dependent/api/v1/acquisitions_orders.t
=> SUCCESS: Tests pass
2. Apply this patch
3. Repeat 1
=> SUCCESS: Tests pass
4. Sign off :-D

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