These are the minimum required vars need to setup HEROKU.
These two vars are essential for Heroku Updater to work. By setting these two vars you can get logs of your heroku app, set var, edit var, delete vars , check dyno usage and update bot.
These two vars are not Mandatory! You can leave them blank too.
HEROKU_API_KEY
To work some Heroku compatible modules, this var value required to Access your account to use `get_log`, `usage`, `update` etc etc commands.
You can fill this var using your API key or Authorization token.