According to https://gitlab.com/Bitergia/c/FAQ/tree/master/sources this will require adding a github data source to https://gitlab.com/Bitergia/c/Wikimedia/sources/raw/master/projects.json , but I imagine that more needs to be done server-side to also make a "Github" dashboard appear on https://wikimedia.biterg.io/ next to "Overview | Git | Gerrit | ...".
To be discussed with Bitergia in https://gitlab.com/Bitergia/c/Wikimedia/support/issues/56