Unlike ESP8266-related devices, flashing Arduino-based devices requires that we use a tool that isn't native Python. As a result, the tool has to be installed manually as a root user - something that can't be done on an already installed instance of Fermentrack. Thankfully, the fix takes less than a minute, and can be accomplished in three steps:
Once this is complete, you should no longer see the error message about a missing avrdude installation. Done!