$ git clone -n https://src.fedoraproject.org/rpms/rust-gix-revwalk.git /var/lib/mock/f40-build-2727527-73128/root/chroot_tmpdir/scmroot/rust-gix-revwalk
Cloning into '/var/lib/mock/f40-build-2727527-73128/root/chroot_tmpdir/scmroot/rust-gix-revwalk'...
$ git fetch origin 3bb0683302cbc7ac6045d0575fb8a1eb9ec033e7:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-gix-revwalk
 * [new ref]         3bb0683302cbc7ac6045d0575fb8a1eb9ec033e7 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 3bb0683 Update to version 0.13.0 (rhbz#2253281)