$ git clone -n https://src.fedoraproject.org/rpms/rust-gix-blame.git /var/lib/mock/f42-build-3264143-41244/root/chroot_tmpdir/scmroot/rust-gix-blame
Cloning into '/var/lib/mock/f42-build-3264143-41244/root/chroot_tmpdir/scmroot/rust-gix-blame'...
$ git fetch origin d5f3a009e0270d69a3c7171fc43acbcc27fb7db4:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-gix-blame
 * [new ref]         d5f3a009e0270d69a3c7171fc43acbcc27fb7db4 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at d5f3a00 Initial package (rhbz#2342680)