Don't look inside other classes for values
Don't look inside other classes for values

This adds a little duplication but removes an encapsulation break. If
the names ever become different then calling `config` as a class
will make it all work happily

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