By Herbert Lash and Danilo Masoni NEW YORK/MILAN (Reuters) -A gauge of global equity markets edged higher on Tuesday while 10-year U.S. Treasury yields slid from the 3% level as investors remained cautious, expecting the Federal Reserve to hike rates by the most in a single day since 2000 to curb inflation. Feeding inflation worries, data showed U.S. job openings hit a record in March as worker shortages persisted. This suggested employers may need to raise wages, which likely would increase consumer prices. Investors expect the Fed to hike rates by half a percentage point on Wednesday, and to…