fixing misunderstanding (#713)

* fixing misunderstanding

api-platform/admin#73

* Update getting-started.md

Author: numediaweb

admin/getting-started.md

@@ -27,7 +27,9 @@ Edit the `src/App.js` file like the following:
 import React from 'react';
 import { HydraAdmin } from '@api-platform/admin';
 
-export default () => <HydraAdmin entrypoint="https://demo.api-platform.com"/>; // Replace with your own API entrypoint
+// Replace with your own API entrypoint: if https://example.com/api/books is the path
+// to the collection of book resources, then the entrypoint is https://example.com/api
+export default () => <HydraAdmin entrypoint="https://demo.api-platform.com"/>;
 ```
 
 Be sure to make your API send proper [CORS HTTP headers](https://developer.mozilla.org/en-US/docs/Web/HTTP/CORS) to allow