$ git clone -n https://src.fedoraproject.org/rpms/rust-poly1305.git /var/lib/mock/f45-build-43924-809/root/chroot_tmpdir/scmroot/rust-poly1305
Cloning into '/var/lib/mock/f45-build-43924-809/root/chroot_tmpdir/scmroot/rust-poly1305'...
$ git fetch origin 57d8ccca4a1e759a2acd65a80f95197fe3ed82e8:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-poly1305
 * [new ref]         57d8ccca4a1e759a2acd65a80f95197fe3ed82e8 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 57d8ccc Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild