GRAND FORKS — Every time the caution flag came out, there were sighs and groans at River Cities Speedway. But there was no reason to fret about the restarts. Kenna Breidenbach had it under control. Breidenbach, a 17-year-old Grand Forks Red River student, stole the show at River Cities Speedway on Friday night, winning the Midwest Modifieds feature over Roseau's Taylor Jacobson and Winnipeg's Austin Hunter, the track's defending points champion.…