@Override
    protected AWSAppTestAsync build(AwsAsyncClientParams params) {
        return new AWSAppTestAsyncClient(params);
    }
Construct an asynchronous implementation of AWSAppTestAsync using the current builder configuration.

@param params
       Current builder configuration represented as a parameter object.
@return Fully configured implementation of AWSAppTestAsync.
aws-java-sdk-apptest/src/main/java/com/amazonaws/services/apptest/AWSAppTestAsyncClientBuilder.java