You will have to open your repo in GitHub first then go to the settings, there you will find secrets. Create a new secret and name the variable like I have named HEROKU_API_KEY and put the value there. The best things about this is only the collaborator can see the value of the secret variables.
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You will have to open your repo in GitHub first then go to the settings, there you will find secrets. Create a new secret and name the variable like I have named HEROKU_API_KEY and put the value there. The best things about this is only the collaborator can see the value of the secret variables.