President Joe Biden took a jab at former President Donald Trump for confusing Republican presidential candidate Nikki Haley with former Speaker Nancy Pelosi (D-Calif.) during a recent campaign rally. What Happened: Biden, on Sunday, took a potshot at Trump for the mix-up, tweeting, “I don’t agree with Nikki Haley on everything, but we agree on this much: She is not Nancy Pelosi.” The tweet included a campaign ad that criticized Trump for the mix-up and raised concerns about his mental fitness. The ad featured comments from Haley, the former South Carolina governor and U.N. ambassador under Tru…