@Override
    public List<ValidationEvent> validate(Model model) {
        return model.shapes(ServiceShape.class)
                .map(service -> validate(model, service))
                .flatMap(List::stream)
                .collect(Collectors.toList());
    }
Validates if authorizers traits are well-defined.
smithy-aws-apigateway-traits/src/main/java/software/amazon/smithy/aws/apigateway/traits/AuthorizersTraitValidator.java