$ git clone -n https://src.fedoraproject.org/rpms/fvwm3.git /var/lib/mock/f42-build-side-1-3585423-46904/root/chroot_tmpdir/scmroot/fvwm3
Cloning into '/var/lib/mock/f42-build-side-1-3585423-46904/root/chroot_tmpdir/scmroot/fvwm3'...
$ git fetch origin 2effd3ffb4963a3baf101a377fbe693e225a1557:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/fvwm3
 * [new ref]         2effd3ffb4963a3baf101a377fbe693e225a1557 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 2effd3f FVWM3 ver. 1.1.3