Veteran political strategist Mark McKinnon, a Republican, was blown away by Kamala Harris’ “dominant” performance in her debate against Donald Trump. The vice president appeared to trigger the former president by claiming Trump fans walked out of his rallies “out of exhaustion and boredom,” and the GOP nominee made baseless and bizarre claims about Jan. 6, Hunter Biden, migrants eating pets and gender reassignment surgeries for illegal immigrants in prison. “I mean, I’ve seen, watched, prepped for does and dozens and dozens a debates,” said McKinnon, who worked for George W. Bush and John McCa…