Magento 2 Error – Error on Running update/cron.php

I'm getting an error on running update/cron.php

I setup the cronjob according to the documentation. But it gives the following error:

PHP Warning: require_once(update/vendor/autoload.php): failed to open stream: No such file or directory in update/app/bootstrap.php on line 13

PHP Fatal error: require_once(): Failed opening required 'update/vendor/autoload.php' (include_path='.:') in update/app/bootstrap.php on line 13

I found that the path update/vendor/autoload.php is wrong. The autoload.php should be at /vendor instead. Is it a bug?