BUREAU OF CULTURAL AFFAIRS. Jonah Goldberg adds to his colleague's list of conservatively-correct shows "South Park," "Buffy the Vampire Slayer," and "The Dave Chapelle Show." No explanation is provided -- Goldberg is steamrollin' on his way to a demand for affirmative action for conservatives, about which more later -- but one ventures to guess that they pass the red litmus test because Buffy has values 'cause she fights evil and stuff, "South Park" proceeds from the loins of the sainted Parker and Stone, and Chapelle sometimes makes fun of black people, something