Update summary title to "Discount" instead of coupon(s) and ensure negative fees are reflected in order details#62454

opr merged 6 commits intotrunkwoocommerce/woocommerce:trunkfrom

wooplug-5995-2-display-issues-to-make-the-order-detail-page-synchronizedwoocommerce/woocommerce:wooplug-5995-2-display-issues-to-make-the-order-detail-page-synchronizedCopy head branch name to clipboard