Even feeding questions to a black radio host couldn’t save President Joe Biden from embarrassing himself — and it’s cost the host her job. WURD-AM in Philadelphia announced in a statement on Sunday that it had “mutually agreed to part ways” with Andrea Lawful-Sanders, the host who interviewed Biden last Wednesday. Lawful-Sanders’ interview with the president had initially gone viral after the president tripped over his own brain again, telling the interviewer that he was a female of color. “By the way, I’m proud to be, as I said, the first vice president, the first black woman to serve with a…