NEW YORK — There may not have been the crowds chanting heatedly at the opponents. It was a Monday night and the Yankees got off to a slow start against the team with the worst record in baseball, but there was no let down at the Stadium. The Bombers rallied with a six-run seventh inning in the series-opener to beat the A’s 9-5. The Yankees (54-20) have won two games in a row after losing two over the weekend to the Astros. It was their major-league leading 23rd come-from-behind win and their second in as many days. They maintained the best record in baseball, while the A’s (25-50) became the f…