Add errbit ENV vars to publishing-api config
Add errbit ENV vars to publishing-api config

https://trello.com/c/HfNnOLFJ

the errbit host, API key and environment name are used by the
gobrake client in errbit. these differ across environments and
need to be configured accordingly.

we won't require errbit in development, so no need to configure.

alphagov/govuk-puppet,alphagov/govuk-puppet,alphagov/govuk-puppet,alphagov/govuk-puppet,alphagov/govuk-puppet,alphagov/govuk-puppet