MILWAUKEE — What started with Steven Matz zeroing in on his first chance to make a better second impression with his new club became the first true showcase of the season for how the Cardinals intend to end taut games. The Cardinals’ bullpen inherited a one-run lead in the sixth inning Saturday, got a vital boost with another run in the eighth, and shepherded the game through the final 10 outs. Right-hander Giovanny Gallegos, the Cardinals’ closer who is advertised as available in any inning needed, took over in the eighth and secured a 2-1 victory against Milwaukee at American Family Field. P…