Take advantage of DD lightweight IoT agent

[mrpher]

I'd like to suggest this repo be updated with Datadog's new IoT agent which is lighter weight and more specifically geared towards Balena's use case.
More info:
https://docs.datadoghq.com/agent/iot/
https://www.datadoghq.com/blog/datadog-iot-agent/

[vipulgupta2048]

Thanks @mrpher for reaching out with this information. Would you be willing to open a PR to add DD's IoT agent and update the repository. We would greatly appreciate help in keeping this example updated. Thanks again!