Nice, thanks for sharing @Tomas. You can even add a cron job with the root user to reboot the server instance.
sudo crontab -e
and add a line like: (to run the restart one minute after the certificate update)
6 1 * * * service snap.thinger-maker-server.thingerd restart
It should work! However, restarting the server and updating certificates every day seems to be unnecessary. If I remember fine, those certificates are valid for 3 months, is it?