Provide integration with Eclipse Hawkbit

Eclipse is the home of several interesting IoT specific projects that are candidates for integration with SysOTA. One of those projects is Eclipse Hawkbit: https://www.eclipse.org/hawkbit/

Given that SysOTA is based on RAUC: https://rauc.io/ - and thanks to the RAUC handler system, interacting with RAUC can keep SysOTA in the loop, exiting RAUC-Hawkbit integrations may be sufficient for a good experience. We should explore this and, in the end provide reference architecture comprising Oniro OS, RAUC update bundles, SysOTA system state management and Hawkbit agent driving RAUC as a complete solution.