Thanks for reporting, @sonic. This issue was already reported and fixed for upcoming updates. (I reckon the ticket will be updated soonish.) In the mean time, it is possible to use update via terminal once as described or to delete (resp. re-name) config/packages/shopware.yaml in order to see updates in admin panel again.
BTW: it is highly appreciated to respond in the language of the thread opening. Otherwise it is going to become max confusing for everybody not speaking German. Thanks for that 