Shota Imanaga held the St. Louis Cardinals to a run on four hits over seven innings to earn his seventh win Saturday as the Chicago Cubs triumphed 5-1. Imanaga (7-1) struck out six with a hit batsman in a strong 103-pitch outing at Wrigley Field, surrendering his only run in the fourth inning when Alec Burleson hit a leadoff double and came home on Nolan Arenado’s sacrifice fly to open the scoring. The Cubs scored two runs in the home half to take the lead before Imanaga had two runners on bases for the first time in the seventh. The southpaw escaped the jam by getting Dylan Carlson to fly out…