Bug 25663: Remove Koha::RefundLostItemFeeRule and uses

Bug 25663: Remove Koha::RefundLostItemFeeRule and uses

This patch replaces all calls to RefundLostItemFeeRules with
Koha::CirculationRules->get_lostreturn_policy and removes the module it
makes redundant.

Test plan
1/ Confirm that there are no longer any uses of RefundLostItemFeeRules
in the codebase
2/ Confirm circulation tests still all pass
3/ Confirm you can still set and unset the lost return rules
4/ Signoff

Signed-off-by: Kyle M Hall <kyle@bywatersolutions.com>
Signed-off-by: Tomas Cohen Arazi <tomascohen@theke.io>
Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>