fix: fix typo

Author: Gumichocopengin8

web/src/App.tsx

@@ -6,7 +6,7 @@ function App() {
   return (
     <Flex direction={'column'} align={'center'} style={{ height: '100vh' }}>
       <Heading as='h1' size={'7'} style={{ padding: '4rem' }}>
-        MNNIST Ineferance
+        MNIST Ineferance
       </Heading>
       <CanvasBoard />
     </Flex>