Tweak environment detection in user creation task
Tweak environment detection in user creation task

This change will detect the environment using HostEnv for the user creation
rake task. The Dev env in AWS is running with RAILS_ENV=production so when
seed/migration tasks are running currently no users are being created.

ministryofjustice/parliamentary-questions,ministryofjustice/parliamentary-questions,ministryofjustice/parliamentary-questions,ministryofjustice/parliamentary-questions,ministryofjustice/parliamentary-questions