Update code-sample setting guide sort

Author: alallema

.code-samples.meilisearch.yaml

@@ -273,6 +273,13 @@ settings_guide_displayed_1: |-
       'release_date',
     ]
   })
+settings_guide_sortable_1: |-
+  client.index('books').updateSettings({
+    sortableAttributes: [
+      'author',
+      'price'
+    ]
+  })
 add_movies_json_1: |-
   const movies = require('./movies.json')
   client.index('movies').addDocuments(movies).then((res) => console.log(res))