(PUP-1281) Ensure don't override stdout/stderr (windows/ruby2)

This provides a more deterministic set of specs that determine whether we have
wrapped $stderr/$stdout or not based on ruby version.
Merge remote-tracking branch 'rob/ticket/master/PUP-1281-colors-specs'

* rob/ticket/master/PUP-1281-colors-specs:
  (PUP-1281) Ensure don't override stdout/stderr (windows/ruby2)