Not all date-time properties are represented as UTC

Overview:

FOLIO's guidelines state that module API's should represent date-time properties in UTC.

A recent change caused that to stop being the case for mod-circulation.

Steps to Reproduce:

1. Execute the following commands

   git checkout 1f5d43c0527e44255ae1d9bf63562625be501685
   mvn -Duser.timezone=America/New_York -Dtest=api.loans.CheckInByBarcodeTests test
   

Expected Results: All tests pass and date-time property is represented in UTC
Actual Results:
Additional Information: This issue was obscured by this pull request

Interested parties: kday felkerk julianladisch Illia Dolzhenko