update Intl note, #839 (comment)

README.md

@@ -2816,4 +2816,4 @@ console.log(getIteratorMethod({})); // undefined
 - ES `String#normalize` is not a very useful feature, but this polyfill will be very large. If you need it, you can use [unorm](https://github.com/walling/unorm/).
 - ES `Proxy` can't be polyfilled, you can try [`proxy-polyfill`](https://github.com/GoogleChrome/proxy-polyfill) which provides a very little subset of features.
 - `window.fetch` is not a cross-platform feature, in some environments, it makes no sense. For this reason, I don't think it should be in `core-js`. Looking at a large number of requests it *might be*  added in the future. Now you can use, for example, [this polyfill](https://github.com/github/fetch).
-- ECMA-402 `Intl` is missed because of the size. You can use [this polyfill](https://github.com/andyearnshaw/Intl.js/).
+- ECMA-402 `Intl` is missed because of the size. You can use [those polyfills](https://formatjs.io/docs/polyfills).