@Override
    public void shutdown() {
        super.shutdown();
        if (waiters != null) {
            waiters.shutdown();
        }
    }
Invoke the request using the http client. Assumes credentials (or lack thereof) have been configured in the
ExecutionContext beforehand.
aws-java-sdk-glacier/src/main/java/com/amazonaws/services/glacier/AmazonGlacierClient.java