chore: Update required NextJS version in readme (#234)

Author: benjick

README.md

@@ -116,7 +116,7 @@ The `getServerSideProps`, `getInitialProps`, and `getStaticProps` data hooks pro
 
 Thankfully, Superjson is a perfect tool to bypass that limitation!
 
-### Next.js SWC Plugin (experimental, v12.2 or above)
+### Next.js SWC Plugin (experimental, v13 or above)
 
 Next.js SWC plugins are [experimental](https://nextjs.org/docs/advanced-features/compiler#swc-plugins-experimental), but promise a significant speedup.
 To use the [SuperJSON SWC plugin](https://github.com/blitz-js/next-superjson-plugin), install it and add it to your `next.config.js`: