docs(CSidebar): update api documentation

Author: mrholek

docs/4.0/api/CSidebar.api.mdx

@@ -7,4 +7,4 @@
 | **position** | Place sidebar in non-static positions. | `"fixed" | "sticky"` | - |
 | **size** | Size the component small, large, or extra large. | `"sm" | "lg" | "xl"` | - |
 | **unfoldable** | Expand narrowed sidebar on hover. | `boolean` | - |
-| **visible** | Toggle the visibility of sidebar component. | `boolean` | - |
+| **visible** | Toggle the visibility of sidebar component. | `boolean` | true |