Hey @gaocegege :) You already have the necessary git command and regex defined:
https://github.com/gaocegege/maintainer/blob/5f09778bcf080f106b77c2f07f6fa3a94bb47688/cmd/contributor.go#L34-L51
But you don't use them. I don't think that many people want to create a GitHub API token just for using maintainer. So this should be optional