gnu: python-blessings: Update comment on test suite.

* gnu/packages/terminals.scm (python-blessings): Test suite has been revised.
[arguments]: Change comment to reflect change in test suite regarding TTY.
[native-inputs]: Pass python-six, which is required for test suite.

gnu/packages/terminals.scm

@@ -839,10 +839,11 @@ (define-public python-blessings
          "0z8mgkbmisxs10rz88qg46l1c9a8n08k8cy2iassal2zh16qbrcq"))))
     (build-system python-build-system)
     (arguments
-     ;; TODO: For py3, 2to2 is used to convert the code, but test-suite fails
+     ;; FIXME: Test suite is unable to detect TTY conditions.
      `(#:tests? #f))
     (native-inputs
-     `(("python-nose" ,python-nose)))
+     `(("python-nose" ,python-nose)
+       ("python-six" ,python-six)))
     (home-page "https://github.com/erikrose/blessings")
     (synopsis "Python module to manage terminal color, styling, and
 positioning")