Update and rename intro_sqlalchemy.md to sqlalchemy_aggregation.md

contrib/database/sqlalchemy_aggregation.md

@@ -102,4 +102,4 @@ min_price = session.query(func.min(Product.price)).scalar()
 print(f'Minimum price of products: {min_price}')
 ```
 
-In general, the aggregation functions can be implemented by utilising the **session** object to execute the desired query on the table present in a database using the **query()** method. The **scalar()** method is called on the query object to execute the query and return a single value
+In general, the aggregation functions can be implemented by utilising the **session** object to execute the desired query on the table present in a database using the **query()** method. The **scalar()** method is called on the query object to execute the query and return a single value