$ git clone -n https://src.fedoraproject.org/rpms/rust-arrow-json.git /var/lib/mock/f45-build-40149-768/root/chroot_tmpdir/scmroot/rust-arrow-json
Cloning into '/var/lib/mock/f45-build-40149-768/root/chroot_tmpdir/scmroot/rust-arrow-json'...
$ git fetch origin 4ca412415881498628e1c58bc0f33697e48dd340:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-arrow-json
 * [new ref]         4ca412415881498628e1c58bc0f33697e48dd340 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 4ca4124 Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild