Enable Golang-migrated features on live environments

With omnibus-gitlab#4207 (closed), #178 (closed), and #179 (closed), we should be able to enable the Golang versions of our discover and 2fa_recovery_codes features on our live environments: dev, staging, canary, and production.

We should roll the features out across these environments in order, verifying that everything works correctly at each before moving on to the next.