$ git clone -n https://src.fedoraproject.org/rpms/rust-uu_df.git /var/lib/mock/f41-build-810472-146712/root/chroot_tmpdir/scmroot/rust-uu_df
Cloning into '/var/lib/mock/f41-build-810472-146712/root/chroot_tmpdir/scmroot/rust-uu_df'...
$ git fetch origin eb99006bd02675afb938259e6fe27e28b65ce63f:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-uu_df
 * [new ref]         eb99006bd02675afb938259e6fe27e28b65ce63f -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at eb99006 Rebuild with Rust 1.78 to fix incomplete debuginfo and backtraces