$ git clone -n https://src.fedoraproject.org/rpms/rust-jpegxl-rs.git /var/lib/mock/f45-build-45163-821/root/chroot_tmpdir/scmroot/rust-jpegxl-rs
Cloning into '/var/lib/mock/f45-build-45163-821/root/chroot_tmpdir/scmroot/rust-jpegxl-rs'...
$ git fetch origin b50f0a70e276760addce7853a4cd688fc24cf5e8:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-jpegxl-rs
 * [new ref]         b50f0a70e276760addce7853a4cd688fc24cf5e8 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at b50f0a7 Update to version 0.14.0+libjxl-0.11.2