kill some govuk_platform usage
kill some govuk_platform usage

since we no longer have an ec2 production, we can simplify this.

it will disappear entirely once we have no ec2 environments left.

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