$ git clone -n https://src.fedoraproject.org/rpms/jfreechart.git /var/lib/mock/f38-build-side-42-init-devel-779801-27889/root/chroot_tmpdir/scmroot/jfreechart
Cloning into '/var/lib/mock/f38-build-side-42-init-devel-779801-27889/root/chroot_tmpdir/scmroot/jfreechart'...
$ git fetch origin 76a294c738e5a3c6b793a7a4435c7c5aff4c21b2:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/jfreechart
 * [new ref]         76a294c738e5a3c6b793a7a4435c7c5aff4c21b2 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 76a294c Update to version 1.5.4