[docs] fixed typo (#956)

lonix1 · web-flow · commit af9f5ea97ddd · 2022-09-09T13:33:06.000+02:00
diff --git a/docs/input/widgets/tree.md b/docs/input/widgets/tree.md
@@ -43,7 +43,7 @@ AnsiConsole.Write(root);
 ## Collapsing nodes
 
 ```csharp
-root.AddNode("Label").Collapsed();
+root.AddNode("Label").Collapse();
 ```
 
 ## Appearance
