4757 endpoint for notification of validation completion
Created by: teddywing
A new API endpoint at /api/v1/compliance_check_sets/:id. This will be called by the Java validation program when it finishes.
The endpoint takes care of work that needs to happen post validation. For now, that's updating the status of the ComplianceCheckSet based on the status of its associated ComplianceCheckResources. Eventually this will be extended to handle post validation work during an OAT merge.