The DOKKU_APP_TYPE has long since ceased to be the correct way to specify the builder for the application. It's only usage has been during the detection phase, specifically to ensure that the herokuish plugin injects the correct docker arguments during the build. As such, it is safe to migrate away to a property in a patch release.
Users that seek to set a specific builder should use 'dokku builder:set $APP selected' instead.
Refs #7863
When developing Dokku, it is useful to use a real domain to test actual functionality. This is impossible if the domain is hardcoded to dokku.me in testing.
