String getResponse() {
            return new String(Base64.encodeBase64(getBytes()), StandardCharsets.US_ASCII);
        }
Returns the response that has been generated after shrinking the
array if required and base64 encodes the response.

@return The response as above.
httpclient5/src/main/java/org/apache/hc/client5/http/impl/auth/NTLMEngineImpl.java