$ git clone -n https://src.fedoraproject.org/rpms/rust-cargo-readme.git /var/lib/mock/f41-build-811027-147135/root/chroot_tmpdir/scmroot/rust-cargo-readme
Cloning into '/var/lib/mock/f41-build-811027-147135/root/chroot_tmpdir/scmroot/rust-cargo-readme'...
$ git fetch origin 9582827666fccf7a057fd40b6fbec3b06193048c:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-cargo-readme
 * [new ref]         9582827666fccf7a057fd40b6fbec3b06193048c -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 9582827 Rebuild with Rust 1.78 to fix incomplete debuginfo and backtraces