Remove gom
Remove gom

We are using `godep` now. This is no longer needed. i[We did discuss this
with the last upgrade](https://github.com/gds-attic/ci-puppet/pull/447)
but deferred it while we evaluated `godep`.

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