code: public function validate(RequestInterface $request, $secret)
      {
          $signature   = $request->getHeader('X-Hub-Signature');
          $requestBody = $request->getBody();
          $requestBody->rewind();
  
          $payload = $requestBody->getContents();
  
          if (!$this->validateSignature($signature, $payload, $secret)) {
              throw new InvalidGitHubRequestSignatureException($request, $signature);
          }
      }
docs: {@inheritdoc}