PARMA, Italy — Coco Gauff advanced to the semifinals of the Emilia-Romagna Open after beating Amanda Anisimova 6-3, 6-3 on Thursday in a match between two American teenagers. The 17-year-old Gauff, who last week reached the Italian Open semifinals for her career-best result on clay, came from 3-0 down in the second set. “And then I honestly just decided to …