Changes to Download Brand evidence

added the pattern ^B[A-Z0-9]{6}$ to the path request parameter brand_id

the response's body type changed from no type to object for status 404

removed RecordNotFoundErrorResponse subschema #2 from the response body allOf list for the response status 404

added the non-success response with the status 400

added the non-success response with the status 401

added the non-success response with the status 403

added the required property message to the response with the 404 status

added the required property success to the response with the 404 status