FAL-1755 Fix update_discussions_map example call
apply_async args value must be a tuple. See https://docs.celeryproject.org/en/stable/reference/celery.app.task.html#celery.app.task.Task.apply_async
apply_async args value must be a tuple. See https://docs.celeryproject.org/en/stable/reference/celery.app.task.html#celery.app.task.Task.apply_async