docs(graphql): snippets split, improved, and lint (#1287)

Author: heitorlessa

.pre-commit-config.yaml

@@ -9,7 +9,6 @@ repos:
     hooks:
       - id: check-merge-conflict
       - id: trailing-whitespace
-      - id: end-of-file-fixer
       - id: check-toml
   - repo: local
     hooks:

docs/core/event_handler/api_gateway.md

@@ -387,7 +387,7 @@ You can instruct API Gateway handler to use a custom serializer to best suit you
 
 As you grow the number of routes a given Lambda function should handle, it is natural to split routes into separate files to ease maintenance - That's where the `Router` feature is useful.
 
-Let's assume you have `app.py` as your Lambda function entrypoint and routes in `split_route_module.py`, this is how you'd use the `Router` feature.
+Let's assume you have `split_route.py` as your Lambda function entrypoint and routes in `split_route_module.py`. This is how you'd use the `Router` feature.
 
 === "split_route_module.py"