It is unlikely your contact details are copyrightable in the first place, in the US anyway.
It is unlikely you have the legal ability to prohibit someone from publishing your contact details... _under copyright_. There may be other laws related to privacy that are relevant.
If the publisher in question is referring to "public domain", they probably have no idea what they're doing legally, "public domain" is unlikely to be relevant.
Practically, I would complain to Github itself, who is likely to frown at them doing that, and cut off their API access or what have you.
It is unlikely you have the legal ability to prohibit someone from publishing your contact details... _under copyright_. There may be other laws related to privacy that are relevant.
If the publisher in question is referring to "public domain", they probably have no idea what they're doing legally, "public domain" is unlikely to be relevant.
Practically, I would complain to Github itself, who is likely to frown at them doing that, and cut off their API access or what have you.