Update example query document link

Author: yothinix

examples/cookbook-plain/README.md

@@ -60,5 +60,5 @@ Now you should be ready to start the server:
 Now head on over to
 [http://127.0.0.1:8000/graphql](http://127.0.0.1:8000/graphql)
 and run some queries!
-(See the [Graphene-Django Tutorial](http://docs.graphene-python.org/projects/django/en/latest/tutorial#testing-our-graphql-schema)
+(See the [Graphene-Django Tutorial](http://docs.graphene-python.org/projects/django/en/latest/tutorial-plain/#testing-our-graphql-schema)
 for some example queries)

examples/cookbook/README.md

@@ -60,5 +60,5 @@ Now you should be ready to start the server:
 Now head on over to
 [http://127.0.0.1:8000/graphql](http://127.0.0.1:8000/graphql)
 and run some queries!
-(See the [Graphene-Django Tutorial](http://docs.graphene-python.org/projects/django/en/latest/tutorial#testing-our-graphql-schema)
+(See the [Graphene-Django Tutorial](http://docs.graphene-python.org/projects/django/en/latest/tutorial-plain/#testing-our-graphql-schema)
 for some example queries)