Sorry for the wrong info in my previous message. I just checked the Bitnami solution's configuration and confirmed that the cron jobs are defined in the /etc/crontab file
sudo cat /etc/crontab
You can edit the configuration there using any command line editor (and sudo)
Where did you find this error? I checked the Magento's cron logs and didn't find that error in any of the log files. Let us know if you find something wrong in the application and I'll create an internal task to review and update the configuration.