Add some properties to NotionDBLoader
diff --git a/libs/langchain/langchain/document_loaders/notiondb.py b/libs/langchain/langchain/document_loaders/notiondb.py
index d7728efcc88da8..e24d6fe555cf69 100644
--- a/libs/langchain/langchain/document_loaders/notiondb.py
+++ b/libs/langchain/langchain/document_loaders/notiondb.py
@@ -130,6 +130,14 @@ def load_page(self, page_summary: Dict[str, Any]) -> Document:
                 )
             elif prop_type == "created_time":
                 value = prop_data["created_time"] if prop_data["created_time"] else None
+            elif prop_type == "checkbox":
+                value = prop_data["checkbox"]
+            elif prop_type == "email":
+                value = prop_data["email"]
+            elif prop_type == "number":
+                value = prop_data["number"]
+            elif prop_type == "select":
+                value = prop_data["select"]["name"] if prop_data["select"] else None
             else:
                 value = None
 

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fix #13356

Add supports following properties for metadata to NotionDBLoader.

- `checkbox`
- `email`
- `number`
- `select`

There are no relevant tests for this code to be updated.
