Changes to Validate source function

the response property allOf[subschema #2]/data became nullable for the status 400

the response property allOf[subschema #2]/data became nullable for the status 401

the response property allOf[subschema #2]/data became nullable for the status 404

the allOf[subschema #2]/data response's property type changed from object to no type for status 400

the allOf[subschema #2]/data response's property type changed from object to no type for status 401

the allOf[subschema #2]/data response's property type changed from object to no type for status 404

the request property payload became nullable

added handlers.Stub to the allOf[subschema #2]/data response property allOf list for the response status 400

added handlers.Stub to the allOf[subschema #2]/data response property allOf list for the response status 401

added handlers.Stub to the allOf[subschema #2]/data response property allOf list for the response status 404

endpoint added