BEIJING—Sport’s highest court on Monday cleared 15-year-old Russian figure skater Kamila Valieva to continue competing in the Beijing Winter Olympics. However, no Olympic medals will be awarded at the women’s singles event on Thursday if Valieva finishes in the top three, with Games chiefs saying they would only present the prizes once her doping case was resolved. The Court of Arbitration for Sport (CAS) upheld an earlier decision by the Russian Anti-Doping Agency (RUSADA) to lift a ban on Valieva, who tested positive for the banned heart medication Trimetazidine on Dec. 25 at the Russian nationals. The result of the positive drug test was not revealed until Feb. 8 after Valieva helped the Russian Olympic Committee win the team gold at the Winter Games, dazzling the world with the first quad jumps ever completed in the women’s Olympic competition. The skating prodigy took to the Beijing ice half an hour …