private static byte[] hmacSha256(byte[] key, String value) {
        try {
            Mac mac = Mac.getInstance("HmacSHA256");
            mac.init(new SecretKeySpec(key, "HmacSHA256"));
            return mac.doFinal(value.getBytes(StandardCharsets.UTF_8));
        }
        catch (NoSuchAlgorithmException | InvalidKeyException e) {
            throw new UnsupportedOperationException(e.getMessage(), e);
        }
    }
Task 4.
<a href="https://docs.aws.amazon.com/general/latest/gr/sigv4-add-signature-to-request.html">Add the Signing Information to the Request</a>
src/main/java/io/fabric8/maven/docker/access/ecr/AwsSigner4.java