$ git clone -n https://src.fedoraproject.org/rpms/nest.git /var/lib/mock/f41-build-856809-167776/root/chroot_tmpdir/scmroot/nest
Cloning into '/var/lib/mock/f41-build-856809-167776/root/chroot_tmpdir/scmroot/nest'...
$ git fetch origin 99e1bd668064bdcf41304f443effcd1d2cc60a5c:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/nest
 * [new ref]         99e1bd668064bdcf41304f443effcd1d2cc60a5c -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 99e1bd6 Update to 3.8 upstream release