$ git clone -n https://src.fedoraproject.org/rpms/fbrnch.git /var/lib/mock/f41-build-side-1-2786443-32610/root/chroot_tmpdir/scmroot/fbrnch
Cloning into '/var/lib/mock/f41-build-side-1-2786443-32610/root/chroot_tmpdir/scmroot/fbrnch'...
$ git fetch origin 1d299c333f76606f616f815b6af1f6a7f2ef461e:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/fbrnch
 * [new ref]         1d299c333f76606f616f815b6af1f6a7f2ef461e -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 1d299c3 update to 1.5 with new fedora-releases, select-rpms, say deps