docs(build): fix chunking strategy info (#7253)

docs/guide/build.md

@@ -45,7 +45,7 @@ For example, you can specify multiple Rollup outputs with plugins that are only
 
 ## Chunking Strategy
 
-You can configure how chunks are split using `build.rollupOptions.manualChunks` (see [Rollup docs](https://rollupjs.org/guide/en/#outputmanualchunks)). Until Vite 2.7, the default chunking strategy divided the chunks into `index` and `vendor`. It is a good strategy for some SPAs, but it is hard to provide a general solution for every Vite target use case. From Vite 2.8, `manualChunks` is no longer modified by default. You can continue to use the Split Vendor Chunk strategy by adding the `splitVendorChunkPlugin` in your config file:
+You can configure how chunks are split using `build.rollupOptions.output.manualChunks` (see [Rollup docs](https://rollupjs.org/guide/en/#outputmanualchunks)). Until Vite 2.8, the default chunking strategy divided the chunks into `index` and `vendor`. It is a good strategy for some SPAs, but it is hard to provide a general solution for every Vite target use case. From Vite 2.9, `manualChunks` is no longer modified by default. You can continue to use the Split Vendor Chunk strategy by adding the `splitVendorChunkPlugin` in your config file:
 
 ```js
 // vite.config.js