I just pushed an update that clears the warning, thanks!
I don’t know how much longer this one should be supported since I really don’t think it covers the range of legal requirements that are needed out there. That’s why there’s a big scary banner in the OP:
At this time, it is highly unlikely that this theme component will be enough to comply with GDPR regulations. This is particularly the case if you are using services that introduce 3rd-party cookies. It is highly recommended that you talk to your lawyer and figure out your individual needs
There is the Cookie Consent, GDPR, and Discourse guide that should have more complete options. Though, it looks like some parts of it are due for a refresh soon as well.