John Minchillo/AP Images Donald Trump Jr. jumped into a Twitter fight on Tuesday between Rep. Alexandria Ocasio-Cortez and Barstool Sports founder David Portnoy over Portnoy’s threats to fire employees who consider unionizing. Trump Jr. called Ocasio-Cortez’s criticism of Portnoy "the biggest mistake she’s ever made on Twitter." Earlier Tuesday, Ocasio-Cortez accused Portnoy of "likely breaking […]