Fix typo and expand getSeoMeta doc example (#2219)

* Fix typo and expand getSeoMeta doc example

While `matches` is an array, the TS example treats it as an object

The upgrade docs included a more robust example of spreading all the
seo config, adding here as well

* Update packages/hydrogen/src/seo/getSeoMeta.example.tsx

---------

Co-authored-by: = <=>
Co-authored-by: Bret Little <bret.little@gmail.com>

packages/hydrogen/src/seo/getSeoMeta.example.tsx

@@ -22,5 +22,5 @@ export async function loader({context}: LoaderFunctionArgs) {
 
 export const meta: MetaFunction<typeof loader> = ({data, matches}) => {
   // Pass one or more arguments, preserving properties from parent routes
-  return getSeoMeta((matches as any).data.seo, data!.seo);
+  return getSeoMeta((matches as any)[0].data.seo, data!.seo);
 };