Add demo environment checks to `./release`
Add demo environment checks to `./release`

Since we have our demo environment set up as a production env on Heroku pipelines, it will get deployed whenever we do our regular production deploy (yay! intended!). To make sure we don't break things on demo, I've added the same environment-related checks (buildpacks + env vars) that we do for production to the demo app.

[#153856313]

codeforamerica/michigan-benefits,codeforamerica/michigan-benefits,codeforamerica/michigan-benefits,codeforamerica/michigan-benefits