UNIONDALE, N.Y. — Standing in front of a packed arena on New York’s Long Island, former President Donald Trump predicted victory in November in the reliably blue state.“It hasn’t been done for a long time. But we are going to win New York. And that’s the first time in many, many years that a Republican can honestly say it. And we’re going to do it,” Trump vowed.“We have to do it. We do it, and the election nationwide is over,” Trump added as he spoke to what his campaign said was a capacity crowd of roughly 16,000 people packed into an arena in Nassau County, a suburban …