$ git clone -n https://src.fedoraproject.org/rpms/libtiff.git /var/lib/mock/f40-build-1967809-25212/root/chroot_tmpdir/scmroot/libtiff
Cloning into '/var/lib/mock/f40-build-1967809-25212/root/chroot_tmpdir/scmroot/libtiff'...
$ git fetch origin 465cb89e8220032bb9857dc70e83f91f5c8677c3:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/libtiff
 * [new ref]         465cb89e8220032bb9857dc70e83f91f5c8677c3 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 465cb89 revert previous change as per discussion in (#2292047)