$ git clone -n https://src.fedoraproject.org/rpms/rust-matrixmultiply.git /var/lib/mock/f40-build-2681840-67962/root/chroot_tmpdir/scmroot/rust-matrixmultiply
Cloning into '/var/lib/mock/f40-build-2681840-67962/root/chroot_tmpdir/scmroot/rust-matrixmultiply'...
$ git fetch origin a2793ba16662a19ef73a95455b9687ab4da9f637:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-matrixmultiply
 * [new ref]         a2793ba16662a19ef73a95455b9687ab4da9f637 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at a2793ba Rebuilt for https://fedoraproject.org/wiki/Fedora_40_Mass_Rebuild