$ git clone -n https://src.fedoraproject.org/rpms/rust-vergen-lib.git /var/lib/mock/f45-build-35503-695/root/chroot_tmpdir/scmroot/rust-vergen-lib
Cloning into '/var/lib/mock/f45-build-35503-695/root/chroot_tmpdir/scmroot/rust-vergen-lib'...
$ git fetch origin 79ae1e6d0b2d9dd8dec1e46763970b87301649cf:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-vergen-lib
 * [new ref]         79ae1e6d0b2d9dd8dec1e46763970b87301649cf -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 79ae1e6 Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild