Fix UID formatting and update module description in index.yml

Author: JulianePadrao

learn-pr/wwl-data-ai/design-implement-database-objects/index.yml

@@ -1,5 +1,5 @@
 ### YamlMime:Module
-uid: learn-wwl.design-implement-database-objects
+uid: learn.wwl.design-implement-database-objects
 metadata:
   title: Design and implement database objects with SQL
   description: "Learn how to design and implement database objects in SQL Server, Azure SQL, and SQL databases in Microsoft Fabric, including tables, indexes, constraints, and specialized table types."