chore(docs): Fix links to old tutorial docs (gatsbyjs#33605)

Author: gatsbybot

README.md

@@ -36,7 +36,7 @@ _Have another more specific idea? You may want to check out our vibrant collecti
 
     Your site is now running at `http://localhost:8000`!
 
-    _Note: You'll also see a second link: _`http://localhost:8000/___graphql`_. This is a tool you can use to experiment with querying your data. Learn more about using this tool in the [Gatsby tutorial](https://www.gatsbyjs.com/tutorial/part-five/#introducing-graphiql)._
+    _Note: You'll also see a second link: _`http://localhost:8000/___graphql`_. This is a tool you can use to experiment with querying your data. Learn more about using this tool in the [Gatsby tutorial](https://www.gatsbyjs.com/tutorial/part-5/#introducing-graphiql)._
 
     Open the `my-default-starter` directory in your code editor of choice and edit `src/pages/index.js`. Save your changes and the browser will update in real time!