$ git clone -n https://src.fedoraproject.org/rpms/lua-expat.git /var/lib/mock/f45-build-17660-502/root/chroot_tmpdir/scmroot/lua-expat
Cloning into '/var/lib/mock/f45-build-17660-502/root/chroot_tmpdir/scmroot/lua-expat'...
$ git fetch origin 3bfda5cdf506e3d7c90d5abf32655f55e3cf7cbe:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/lua-expat
 * [new ref]         3bfda5cdf506e3d7c90d5abf32655f55e3cf7cbe -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 3bfda5c Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild