By Kyle Wood The Celtics are now heavy favorites at SI Sportsbook to win the NBA title following their Game 3 win over the Warriors that gave them a 2-1 series lead. There’s a new favorite to win the NBA Finals—again. The Celtics took over as heavy title favorites following their 116-100 victory against the Warriors in Game 3 on Wednesday. Jayson Tatum, Jaylen Brown and Marcus Smart each had 20 points in the win, which put Boston up 2-1 in the series and brought their championship odds to -222 on SI Sportsbook. Bet on the NBA Finals at SI Sportsbook Golden State’s championship odds fell to +18…