By Michael Rosenberg The Court of Arbitration for Sport cleared Kamila Valieva to compete in Beijing, sparking questions about the impunity Russia continues to enjoy at the Olympics. BEIJING – Today’s Olympic doping update: Russians are not supposed to take drugs, but they can give them to their kids. That is not a joke. Well, it is. But it’s not supposed to be. The Court of Arbitration for Sport (CAS) decided skater Kamila Valieva can continue to compete in figure skating at the Olympics despite taking a banned heart medication because, according to the IOC, Valieva is a “protected person.” I…