No, "Springfield" is a very common town name (especially one founded not on a body of water or river but in a field with springs), which is why The Simpsons selected it. May as well have been "Anytown, USA".
Anyways, the hoax of Haitian immigrants eating cats was supposedly happening in Springfield, Ohio. It's baseless but that is what Trump fell for, not a Simpsons sketch or anything like that.
This is frankly a really classist remark. No need to bring up her socioeconomic class when there's a perfectly valid reason to dunk on her already (being a Trump supporter and not knowing when the election is).