It isn't unicode. I cloned the repo, this is the commit message in the command line:

  :rotating_light: Lint

Here's the same commit in GitHub: https://github.com/liyasthomas/postwoman/commit/4c9c9a224061...

Why not just use "[rotating_light] Lint" as the commit message? Or even better: "[lint] Make changes recommended by foo lint\n\nThis is the foo command used: ..."