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

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