feat(examples) Add example: SA with Message API preview

[panh99]

No description provided.

[jafermarq]

Suggested change

	rs = sa_aggregator.aggregate(
	[
	driver.create_message(
	content=RecordSet(), # Empty message
	message_type=MessageType.QUERY,
	dst_node_id=nid,
	group_id="",
	)
	for nid in nids
	]
	)
	record = RecordSet() # Empty message
	rs = sa_aggregator.aggregate(
	[
	driver.create_message(
	content=record
	message_type=MessageType.QUERY,
	dst_node_id=nid,
	group_id="",
	)
	for nid in nids
	]
	)

[jafermarq]

Let's say we want to put the same content in all messages. It would normal to define first the RecordSet and then pass it to the create_message() method. however, this wont' work with SA. Triggering errors in the form "cryptography.fernet.InvalidToken"