Former president Donald Trump scoffed at Robert F. Kennedy Jr.’s longshot presidential campaign, dismissing the notion he should set up a debate with the independent candidate. “I don’t know anything about him,” Trump told reporters while taking questions before leaving his hush money trial in Manhattan,RadarOnline.com has learned. “Look, RFK is polling very low. He’s not a serious candidate,” the embattled GOP frontrunner continued. “They say he hurts Biden. I don’t know who he hurts. He might hurt me. I don’t know.” A recent NBC News poll found that RFK Jr.’s candidacy hurts Trump more than …