📝 Add note about Alembic in project generator in SQL docs (#1183)

* Update sql-databases alembic docs

Was helpful to refer to the full-stack project when integrating alembic into my own project

* 📝 Update Alembic note in docs

Co-authored-by: Sebastián Ramírez <tiangolo@gmail.com>

docs/en/docs/tutorial/sql-databases.md

@@ -437,6 +437,8 @@ And you would also use Alembic for "migrations" (that's its main job).
 
 A "migration" is the set of steps needed whenever you change the structure of your SQLAlchemy models, add a new attribute, etc. to replicate those changes in the database, add a new column, a new table, etc.
 
+You can find an example of Alembic in a FastAPI project in the templates from [Project Generation - Template](../project-generation.md){.internal-link target=_blank}. Specifically in <a href="https://github.com/tiangolo/full-stack-fastapi-postgresql/tree/master/%7B%7Bcookiecutter.project_slug%7D%7D/backend/app/alembic/" class="external-link" target="_blank">the `alembic` directory in the source code</a>.
+
 ### Create a dependency
 
 !!! info