Update the json-schema gem version

[mjknight50]

Overview

There is a bug within json-schema where a schema version can be cached. This was addressed in the 5.0.0 update.

Related Issues

https://github.com/department-of-veterans-affairs/va.gov-team/issues/83680

Tasks

• [ ] - Update the gemlock to version 5.0.0 of json-schema

[mjknight50]

The PR for this change is: https://github.com/department-of-veterans-affairs/vets-api/pull/18603