Allows the task to run (or not to run) in a parallel execution thread.
||The application associated with the task is executed in the same thread as the workflow engine, and the latter waits for it to be completed in order to continue processing. This is the default value.
||The application associated with the task is executed in an independent thread and the workflow engine doesn't wait for it to be completed. The application is responsible for notifying the workflow engine through the Complete method when this task processing is completed.