The NBA cracked down on the rowdy behavior of the Dallas bench on Wednesday, fining the Mavs’ $50,000 for violating “team bench decorum” rules in their series-clinching victory over the Phoenix Suns. It’s the second such fine levied against the Mavs in two weeks, and doubled the $25,000 penalty meted out on May 6. NBA president of league operations Byron Spruell said the  amount of the fine reflected the team’s “prior infractions” during the playoffs. […]