Bug 33292: Add unit tests

Bug 33292: Add unit tests

Test plan:
1) In KTD, set ClaimReturnedLostValue to any value
2) Checkout an item to a patron
3) Add a manual invoice to that patron's account against that item barcode
4) In the patron's checkouts table, click the Claim returned button
5) The checkbox will have the option to "Refund previous lost fee"
6) Tick this box and submit
7) Have a look at the patron's transactions. There will now be a new line refunding the lost fee from step 3
8) Run the unit tests
prove t/db_dependent/Circulation/ReturnClaims.t
prove t/db_dependent/api/v1/return_claims.t

Signed-off-by: Kristi Krueger <kkrueger@cuyahogalibrary.org>
Signed-off-by: Lucas Gass <lucas@bywatersolutions.com>
Signed-off-by: Katrin Fischer <katrin.fischer@bsz-bw.de>