Added Documentation for usage with async tools. Fixes fastapi#626

Author: deshetti

docs/advanced/index.md

@@ -4,7 +4,6 @@ The **Advanced User Guide** is gradually growing, you can already read about som
 
 At some point it will include:
 
-* How to use `async` and `await` with the async session.
 * How to run migrations.
 * How to combine **SQLModel** models with SQLAlchemy.
-* ...and more. 🤓
+* ...and more. 🤓