$ git clone -n https://src.fedoraproject.org/rpms/rust-nix0.23.git /var/lib/mock/f40-build-2062901-49167/root/chroot_tmpdir/scmroot/rust-nix0.23
Cloning into '/var/lib/mock/f40-build-2062901-49167/root/chroot_tmpdir/scmroot/rust-nix0.23'...
$ git fetch origin e1aad1bc7837b623bf090de95863ceae796cf1d9:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-nix0.23
 * [new ref]         e1aad1bc7837b623bf090de95863ceae796cf1d9 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at e1aad1b Rebuilt for https://fedoraproject.org/wiki/Fedora_39_Mass_Rebuild