$ git clone -n https://src.fedoraproject.org/rpms/rust-below.git /var/lib/mock/f41-build-768864-13481/root/chroot_tmpdir/scmroot/rust-below
Cloning into '/var/lib/mock/f41-build-768864-13481/root/chroot_tmpdir/scmroot/rust-below'...
$ git fetch origin 031110cbf7cd5872f3864989a804a1517745a783:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-below
 * [new ref]         031110cbf7cd5872f3864989a804a1517745a783 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 031110c Rebuild with Rust 1.78 to fix incomplete debuginfo and backtraces