chore(docs): Fix broken link to gatsby-plugin-guess.js (#34469)

Author: Joshua F Gilmore

docs/docs/how-code-splitting-works.md

@@ -199,4 +199,4 @@ Now the loader can create the full component asset path using [chunkMapping](htt
 
 You may notice that prefetching doesn't prefetch the shared chunks (e.g. `id0` and `id1`). Why? This is a punt. We're guessing that shared chunks will have been loaded earlier for other pages. And if not, then the main page loading logic will download it. It just won't be prefetched.
 
-One more thing, prefetching can be disabled by implementing the [disableCorePrefetching](/docs/reference/config-files/gatsby-browser/#disableCorePrefetching) browser API and returning true. This value is checked in [loader.enqueue](https://github.com/gatsbyjs/gatsby/blob/master/packages/gatsby/cache-dir/loader.js#L242). An example plugin that implements this is [gatsby-plugin-guess-js](https://github.com/gatsbyjs/gatsby/blob/master/packages/gatsby-plugin-guess-js/src/gatsby-browser.js#L3).
+One more thing, prefetching can be disabled by implementing the [disableCorePrefetching](/docs/reference/config-files/gatsby-browser/#disableCorePrefetching) browser API and returning true. This value is checked in [loader.enqueue](https://github.com/gatsbyjs/gatsby/blob/master/packages/gatsby/cache-dir/loader.js#L242). An example plugin that implements this is [gatsby-plugin-guess-js](https://github.com/gatsbyjs/gatsby/tree/master/deprecated-packages/gatsby-plugin-guess-js)(deprecated).