Clean up the syntax use in the govuk.pp class
Clean up the syntax use in the govuk.pp class

These are to make the puppet code consistent with other good
examples throughout this codebase.

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