Changes to * GET /api/v0/exercise-services/client/submissions/:id/download * * Resolves an exercise-slide submission (by the id returned from the submissions list, or by * a submit's `slide_submission_id`) to the files it was made from, so the client can restore * an old submission.

the response property message became required for the status 401

the response property message became required for the status 403

the response property message became required for the status 404

the response property message became required for the status 426

the response property message_key became required for the status 401

the response property message_key became required for the status 403

the response property message_key became required for the status 404

the response property message_key became required for the status 426

the response property type became required for the status 401

the response property type became required for the status 403

the response property type became required for the status 404

the response property type became required for the status 426

removed the required property files from the response with the 200 status

added the required property data_files to the response with the 200 status