TOKYO — The Latest on the Tokyo Olympics, which are taking place under heavy restrictions after a year’s delay because of the coronavirus pandemic. The very first match of the Olympic beach volleyball tournament has been canceled because a Czech player tested positive for COVID-19. Markéta Sluková tested positive earlier this week, knocking her and partner Barbora Hermannova out of the Tokyo Games. The Czechs were supposed to be playing a team from the host country that would have been making its Olympic debut. Instead, the Japanese pair of Megumi Murakami and Miki Ishii earned the victory by default. Sluková...