$ git clone -n https://src.fedoraproject.org/rpms/vfrnav.git /var/lib/mock/f41-build-812171-147723/root/chroot_tmpdir/scmroot/vfrnav
Cloning into '/var/lib/mock/f41-build-812171-147723/root/chroot_tmpdir/scmroot/vfrnav'...
$ git fetch origin cfad4e21bda275f0d1b6fa1b7146cbf55d900c6b:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/vfrnav
 * [new ref]         cfad4e21bda275f0d1b6fa1b7146cbf55d900c6b -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at cfad4e2 Rebuild (gdal)