* Update the coreMQTT submodule pointer
* [coreMQTT Version Update] Include core_mqtt_config.h in mqtt helper files
* Update the coreMQTT-Agent Submodule pointer to the updated fork branch
* Update manifest.yml file
* Add readme for OTA demos transitioning
* Update the pointer to coreMQTT-Agent to the upstream main and update manifest file
* Update manifest file
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Co-authored-by: Rahul Kar <118818625+kar-rahul-aws@users.noreply.github.com>
