NOJIRA: Restore CSFLE use cases on index (#600)

Author: Chris Cho

source/index.txt

@@ -45,16 +45,18 @@ Platforms and Services
 
 Use Cases
 ---------
+
+.. toctree::
+   :maxdepth: 1
+
+   /use-cases/client-side-field-level-encryption-guide
+   /use-cases/client-side-field-level-encryption-local-key-to-kms
+
 ..
-   .. toctree::
-      :maxdepth: 1
-
-      /use-cases/storing-log-data
-      /use-cases/hierarchical-aggregation
-      /use-cases/product-catalog
-      /use-cases/inventory-management
-      /use-cases/category-hierarchy
-      /use-cases/metadata-and-asset-management
-      /use-cases/storing-comments
-      /use-cases/client-side-field-level-encryption-guide
-      /use-cases/client-side-field-level-encryption-local-key-to-kms
+   /use-cases/storing-log-data
+   /use-cases/hierarchical-aggregation
+   /use-cases/product-catalog
+   /use-cases/inventory-management
+   /use-cases/category-hierarchy
+   /use-cases/metadata-and-asset-management
+   /use-cases/storing-comments