$ git clone -n https://src.fedoraproject.org/rpms/kdecoration.git /var/lib/mock/f41-build-824594-154180/root/chroot_tmpdir/scmroot/kdecoration
Cloning into '/var/lib/mock/f41-build-824594-154180/root/chroot_tmpdir/scmroot/kdecoration'...
$ git fetch origin fbf5b38fe0922d8028c52f30ecf620674e881759:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/kdecoration
 * [new ref]         fbf5b38fe0922d8028c52f30ecf620674e881759 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at fbf5b38 rebuild