It looks like the [dlq](https://github.com/cdk-patterns/serverless/blob/a781e501a7dc3a4dea0d22939192bdcb205e7f91/the-state-machine/python/the_state_machine/the_state_machine_stack.py#L51) in the python state machine stack is nowhere referenced. I offer a fix in analogy to the typescript variant in #206.
