@Override
    public List<ApiGatewayConfig.ApiType> getApiTypes() {
        return ListUtils.of(ApiGatewayConfig.ApiType.REST, ApiGatewayConfig.ApiType.HTTP);
    }
Adds the API Gateway x-amazon-apigateway-request-validators object
to the service and x-amazon-apigateway-request-validator to the
service/operations.

<p>Any operation or service shape with the {@link RequestValidatorTrait}
applied to it will cause that operation to have the {@code x-amazon-apigateway-request-validator}
extension, and adds a {@code x-amazon-apigateway-request-validators} extension
to the top-level OpenAPI document.

@see <a href="https://docs.aws.amazon.com/apigateway/latest/developerguide/api-gateway-swagger-extensions-request-validators.html">Request validators</a>
smithy-aws-apigateway-openapi/src/main/java/software/amazon/smithy/aws/apigateway/openapi/AddRequestValidators.java