Update the app’s image to the latest available version.
The update will perform a rolling restart against each Machine, which may result in a brief service disruption.
-a, --app string Application name -c, --config string Path to application configuration file -h, --help help for update --image string Target a specific image --skip-health-checks Skip waiting for health checks between VM updates. -y, --yes Accept all confirmations (also --auto-confirm)