message: ci: fix 'six' Python library download URL
diff: @@ -230,7 +230,7 @@ REPOSITORY_LOCATIONS = dict(
  ),
  six_archive = dict(
  sha256 = "105f8d68616f8248e24bf0e9372ef04d3cc10104f1980f54d57b2ce73a5ad56a",
  - urls = ["https://pypi.python.org/packages/source/s/six/six-1.10.0.tar.gz#md5=34eed507548117b2ab523ab14b2f8b55"],
  + urls = ["https://files.pythonhosted.org/packages/b3/b2/238e2590826bfdd113244a40d9d3eb26918bd798fc187e2360a8367068db/six-1.10.0.tar.gz"],
  ),
  io_opencensus_cpp = dict(
  sha256 = "d6d68704c419a9e892bd1f942e09509ebc5a318499a1abcf2c09734e5dc56e19",
  