Teen-aged Russian figure skater Kamila Valieva has been banned for four years for a doping offence and Russia has been stripped of the 2022 Olympic team event gold medal as a result, the Court of Arbitration for Sport (CAS) said on Monday. Then 15, Valieva helped Russia win the team gold at the Beijing Games two years ago with a stunning performance. But the medal ceremony never took place as it emerged right afterwards that she had tested positive for the banned substance trimetazidine on December 25, 2021, at the Russian championships. Valieva was later cleared by a Russian anti-doping tribu…