CBO: optimizer incorrectly pick index with early order unconditionally

When CBO considers intersect scan from multiple indexes, it currently always pick an index with either order pushdown or early order. For order pushdown this is ok since we only do order pushdown if index has exact spans (no false positives). For early order we should not always prefer an index with early order, since it is possible that there are additional filters that can filter out results from the index scan, and we could have another more selective index that can be used.