By Howard Schneider WASHINGTON (Reuters) – A jump in U.S. monthly job openings has thrown the Federal Reserve another confounding bit of data for its policy meeting this week, with more evidence that rapid interest rate increases have yet to bite hard in the real economy. New data released by the Bureau of Labor Statistics on Tuesday showed firms had 10.7 million job openings at the end of September, a jump of about half a million from August in a number the Fed expects to see move lower as demand in the economy slows. Yields on U.S. Treasury bonds rose after the release of the data, as did be…