docs: clean up async section

Author: heitorlessa

docs/core/event_handler/appsync.md

@@ -538,10 +538,7 @@ This is useful when you want to stop processing immediately in the event of an u
 
 #### Async
 
-Choose the asynchronous batch processor when your objective is to leverage concurrency capabilities without the necessity of preserving records in a specific order.
-
-???+ warning
-    Make sure that preserving the order of the response is not a requirement of your logic.
+Similar to `@batch_resolver` explained in [batch resolvers](#batch-resolvers), you can use `async_batch_resolver` to handle async functions.
 
 === "getting_started_with_batch_async_resolver.py"
   	```python hl_lines="3 7 17"

examples/event_handler_graphql/src/getting_started_with_batch_async_resolver.py

@@ -16,7 +16,7 @@
 }
 
 
-def search_batch_posts(posts: list) -> dict[str, Any]:
+async def search_batch_posts(posts: list) -> dict[str, Any]:
     return {post_id: posts_related.get(post_id) for post_id in posts}
 
 
@@ -29,7 +29,7 @@ async def related_posts(event: list[AppSyncResolverEvent]) -> list[Any]:  # (1)!
     unique_post_ids = list(dict.fromkeys(post_ids))
 
     # Fetch posts in a single batch operation
-    fetched_posts = search_batch_posts(unique_post_ids)
+    fetched_posts = await search_batch_posts(unique_post_ids)
 
     # Return results in original order
     return [fetched_posts.get(post_id) for post_id in post_ids]