Partially revert f0aa3f20f74b3396dd639d251702dc34aabc2729
Partially revert f0aa3f20f74b3396dd639d251702dc34aabc2729

It seems that the Heroku build step has HEROKU_APP_ID but not all
the other environment variables.

>  AssertionError: For a production set up please set the missing variables: DATABASE_URL, TREEHERDER_DJANGO_SECRET_KEY

KWierso/treeherder,KWierso/treeherder,KWierso/treeherder,KWierso/treeherder