$ git clone -n https://src.fedoraproject.org/rpms/perl-Tk.git /var/lib/mock/f41-build-1211673-22574/root/chroot_tmpdir/scmroot/perl-Tk
Cloning into '/var/lib/mock/f41-build-1211673-22574/root/chroot_tmpdir/scmroot/perl-Tk'...
$ git fetch origin e42af4c32f37a40d3a33af337094b1349676abd4:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/perl-Tk
 * [new ref]         e42af4c32f37a40d3a33af337094b1349676abd4 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at e42af4c Remove xorg-x11-xinit from dependencies