Hours after President Joe Biden mistakenly introduced Ukraine’s leader as “President Putin,” Biden flubbed his own running mate’s name, instead calling her “Vice President Trump.” Biden on Thursday took questions live from audience members. The gaffe came in response to a question about whether he had concerns over Vice President Kamala Harris’ chances to beat former President Donald Trump. “Look, I wouldn’t have picked Vice President Trump to be vice president, so I don’t think she’s not qualified to be president. So let’s start there,” said Biden, later adding: “The fact is that the consider…