$ git clone -n https://src.fedoraproject.org/rpms/gnome-mahjongg.git /var/lib/mock/f41-build-836172-158784/root/chroot_tmpdir/scmroot/gnome-mahjongg
Cloning into '/var/lib/mock/f41-build-836172-158784/root/chroot_tmpdir/scmroot/gnome-mahjongg'...
$ git fetch origin 9308785a4060cd56269d71d13bf2fdc4f8a609a3:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/gnome-mahjongg
 * [new ref]         9308785a4060cd56269d71d13bf2fdc4f8a609a3 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 9308785 Update to 47.alpha