message: [MacOSX/Queues] Relax an overly aggressive assertion in a test.
  "Default" is a valid QoS for a thread on older versions of macOS,
  like the one installed in the bot.
  Thanks to Jason Molenda for helping me figuring out the problem.
  <rdar://problem/28346273>
diff: @@ -230,8 +230,9 @@ class TestQueues(TestBase):
  "requested_qos.printable_name",
  stream),
  "Get QoS printable string for unspecified QoS thread")
  + qosName = stream.GetData()
  self.assertTrue(
  - stream.GetData() == "User Initiated",
  + qosName == "User Initiated" or qosName == "Default",
  "unspecified QoS thread name is valid")
  stream.Clear()
  self.assertTrue(
  