[docs] Add a note that ToggleButton exclusive does not enforce selection (#29812)

Author: mmacu

docs/src/pages/components/toggle-button/toggle-button.md

@@ -21,6 +21,8 @@ With exclusive selection, selecting one option deselects any other.
 
 In this example, text justification toggle buttons present options for left, center, right, and fully justified text (disabled), with only one item available for selection at a time.
 
+**Note**: Exclusive selection does not enforce that a button must be active. For that effect see [enforce value set](#enforce-value-set).
+
 {{"demo": "pages/components/toggle-button/ToggleButtons.js"}}
 
 ## Multiple selection