FLORENCE, Italy—Kenya’s Faith Kipyegon set a women’s 1,500 meters world record on Friday by clocking 3:49.11, while world champion Fred Kerley triumphed in the men’s 100 meters at the third Diamond League meeting of the season. Kipyegon shaved almost an entire second off the previous mark of 3:50.07 set by Ethiopia’s Genzebe Dibaba in 2015….