ci: update integration docs (#4400)

Co-authored-by: delucis <[email protected]>
Co-authored-by: Yan Thomas <[email protected]>

src/content/docs/en/guides/integrations-guide/react.mdx

@@ -134,7 +134,7 @@ import ReactComponent from './ReactComponent';
 </ReactComponent>
 ```
 
-If you are using a library that *expects* more than one child element element to be passed, for example so that it can slot certain elements in different places, you might find this to be a blocker.
+If you are using a library that *expects* more than one child element to be passed, for example so that it can slot certain elements in different places, you might find this to be a blocker.
 
 You can set the experimental flag `experimentalReactChildren` to tell Astro to always pass children to React as React vnodes. There is some runtime cost to this, but it can help with compatibility.
 

src/content/docs/en/guides/integrations-guide/vercel.mdx

@@ -223,9 +223,11 @@ export default defineConfig({
 });
 ```
 
-### Per-page functions
+### Function bundling configuration
 
-The Vercel adapter builds to a single function by default. Astro 2.7 added support for splitting your build into separate entry points per page. If you use this configuration the Vercel adapter will generate a separate function for each page. This can help reduce the size of each function so they are only bundling code used on that page.
+The Vercel adapter splits builds into a separate function per route by default. This helps reduce the size of each function, as it only bundles code used on that page.
+
+You can disable this and build to a single function by setting the `functionPerRoute` configuration option to `false`:
 
 ```js
 // astro.config.mjs
@@ -235,7 +237,7 @@ import vercel from '@astrojs/vercel/serverless';
 export default defineConfig({
   output: 'server',
   adapter: vercel({
-    functionPerRoute: true,
+    functionPerRoute: false,
   }),
 });
 ```