message: Fix remote tests broken by r325690
  The patch added an extra argument to the append_to_process_working_directory
  function. I have somehow missed updating this test, and it did not show up
  because the code was only run in remote mode.
diff: @@ -95,7 +95,7 @@ class GenericTester(TestBase):
  if lldb.remote_platform:
  # process launch -o requires a path that is valid on the target
  self.assertIsNotNone(lldb.remote_platform.GetWorkingDirectory())
  - remote_path = lldbutil.append_to_process_working_directory(
  + remote_path = lldbutil.append_to_process_working_directory(self,
  "lldb-stdout-redirect.txt")
  self.runCmd(
  'process launch -- {remote}'.format(remote=remote_path))
  