Update to Rasa 3.x and Action code updates

[rgstephens]

@tholor & @wochinge This PR updates the Rasa bot to 3.x and adds action server code error handling.

[tholor]

Great! Thanks for upgrading this @rgstephens!

[wochinge]

Thanks for updating this, Greg! Left a few small comments.

[julian-risch]

@wochinge What's the current situation here? 🙂 Ready to merge?

[wochinge]

Sorry for the late review. Do have time to wrap up these last comments? Otherwise I'm happy to do so. Thanks for the work 💯

[rgstephens]

Sorry for the slow response and thanks for all the fixes.

[wochinge]

Thanks for the wrap up. Tried it out and works. Only added one fix for an edge condition.
@julian-risch Can you maybe merge this (I don't have write permissions in this repo) and apply the change manually as I also can't write to Greg's repo.

[wochinge]

the answer = response["answers"][1]["answer"] might cause an index error if there are no answers at all or less than 2 answers

Suggested change

	if response["answers"]:
	logger.debug(f"Answers returned by haystack:\n{response}")
	answer = response["answers"][0]["answer"]
	if not answer:
	answer = response["answers"][1]["answer"]
	logger.debug(f"selected answer: {answer}")
	else:
	answer = "No Answer Found!"
	answer = "No Answer Found!"
	for answer_object in response.get("answers") or []:
	current_answer = answer_object["answer"]
	if current_answer:
	answer = current_answer
	logger.debug(f"selected answer: {answer}")
	break