$ git clone -n https://src.fedoraproject.org/rpms/gnome-characters.git /var/lib/mock/f42-build-side-1-3497935-45961/root/chroot_tmpdir/scmroot/gnome-characters
Cloning into '/var/lib/mock/f42-build-side-1-3497935-45961/root/chroot_tmpdir/scmroot/gnome-characters'...
$ git fetch origin ca7ad9704e166e36048411360fe9ac33c213e391:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/gnome-characters
 * [new ref]         ca7ad9704e166e36048411360fe9ac33c213e391 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at ca7ad97 Update to 48.0