[Feature request] Basic ingestion

[IK-Adrian]

Use the basic ingestion for the published messages that are not part of $aws/+.

[gregbreen]

The awslabs topics have been modelled to use the accepted and rejected topic extensions, in the same way as most reserved topics. This wouldn't be possible if basic ingest was used.

The MQTT messaging costs associated with the awslabs/things/thingName/certificate/create and awslabs/things/thingName/certificate/commit topics are a tiny fraction of the overall cost of the solution.

[IK-Adrian]

I understand the messaging cost reduction would be small, but it would also mean that those messages would only be delivered to IoT rules and no other device would be able to subscribe to those topics. I know this doesn't replace authorization but reducing the attack surface is always nice from a sybersecurity point of view.

Despite this, I understand this suggested change has a minor impact.