Including Unternehmensregister (no new data in Bundesanzeiger for 31.12.2021 onwards)

Is it planned and/or possible to integrate ["Unternehmensregister"](https://www.unternehmensregister.de/) the same way the "Bundesanzeiger" is currently implemented? I'm asking this because the current functionality for "Bundesanzeiger" is really helpful, however from 31.12.2021 onwards new data is only going to be published in the "Unternehmensregister" [as stated in their announcement](https://publikations-plattform.de/sp/wexsservlet?page.navid=to_start_ureg&global_data.designmode=pp&global_data.language=de#b). Website structure is pretty much the same with a few changes in the URLs. I'd be really happy if someone could make this work :)

Start by locating the existing Bundesanzeiger integration in the Python package and examining how its URLs and data retrieval are handled. Compare that behavior with Unternehmensregister, then verify that current Bundesanzeiger functionality remains intact and that equivalent Unternehmensregister data can be retrieved.

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