[#51241141] Move -t arg in govuk_spinup
[#51241141] Move -t arg in govuk_spinup

This is a unicornherder argument rather than unicorn. So it would be
appended to the list of args before `--` which delineates the two.

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