$ git clone -n https://src.fedoraproject.org/rpms/libxfce4windowing.git /var/lib/mock/f45-build-17342-498/root/chroot_tmpdir/scmroot/libxfce4windowing
Cloning into '/var/lib/mock/f45-build-17342-498/root/chroot_tmpdir/scmroot/libxfce4windowing'...
$ git fetch origin 17c691fa45f30c56fc74780186cf48b4765107f4:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/libxfce4windowing
 * [new ref]         17c691fa45f30c56fc74780186cf48b4765107f4 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 17c691f Update to 4.20.7