Release 3.9.2.
Revert "Alert users that we're using the API key from the environment"

This reverts commit d09ceab7277a96b9e33b5a24af7ce906f8b372e4.
Release 3.9.3.
Roll back heroku-api gem.
Release version 3.9.4.
run bundle install to update heroku version in Gemfile.lock