$ git clone -n https://src.fedoraproject.org/rpms/cjkuni-ukai-fonts.git /var/lib/mock/f39-build-1721349-41229/root/chroot_tmpdir/scmroot/cjkuni-ukai-fonts
Cloning into '/var/lib/mock/f39-build-1721349-41229/root/chroot_tmpdir/scmroot/cjkuni-ukai-fonts'...
$ git fetch origin 8f7bc83355a806cb0ad8b9316e9a65e377ca4bda:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/cjkuni-ukai-fonts
 * [new ref]         8f7bc83355a806cb0ad8b9316e9a65e377ca4bda -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 8f7bc83 Fix the spec file