$ git clone -n https://src.fedoraproject.org/rpms/apt-cacher-ng.git /var/lib/mock/f41-build-856441-167615/root/chroot_tmpdir/scmroot/apt-cacher-ng
Cloning into '/var/lib/mock/f41-build-856441-167615/root/chroot_tmpdir/scmroot/apt-cacher-ng'...
$ git fetch origin 228314c2307fc76ec7d865a61adddb2e15b9febe:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/apt-cacher-ng
 * [new ref]         228314c2307fc76ec7d865a61adddb2e15b9febe -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 228314c fix bad date