message: Fix promise test
  Different versions of PHP get different Content-Length
diff: @@ -33,11 +33,11 @@ run(function () {
  // You can access each result using the key provided to the unwrap
  // function.
  echo json_decode($results['a']->getBody()->getContents())->data . PHP_EOL;
  - echo $results['b']->getHeaderLine('Content-Length') . PHP_EOL;
  + echo $results['b']->getHeaderLine('Content-Type') . PHP_EOL;
  echo 'Done' . PHP_EOL;
  });
  ?>
  --EXPECT--
  {"data":"hello test1!"}
  -422
  +application/json
  Done
  