When the Trump show heads to Shankweiler, Pennsylvania, on Saturday, it was set to coincide with a tribute to the 90th anniversary of America’s second oldest drive-in movie theater. But now the owners of the Shankweiler’s Drive-In said the small business was forced to switch the day after being informed that the 45th president and presumptive nominee would be stumping in town. “We found out through he news,” Shankweiler’s co-owner Matt McClanahan said in a video posted on their social media site. “Nobody told us this was happening.” Want more breaking political news? Click for the latest headl…