[Django]-How do I include nginx and gunicorn configuration files in source control on Digital Ocean?

You can add your nginx config file to your repository

mv /etc/nginx/sites-available/django /src/my_project/nginx/django
git add /src/my_project/nginx/django

Then create a symlink.

ln -s /src/my_project/nginx/django /etc/nginx/sites-enabled/django

You can do the same for your gunicorn config.