There's no autoupdater that will do the work for you because mailwizz isn't a simple script with just a few slim database tables.
When you have a 10GB database, last thing you want is an autoupdater to kick in and screw things because it can take several hours and the browser will timeout. It's simply too risky to go that road.
Instead, when a new version of the app is released, you will see in your dashboard, then you'll follow the instructions from: