docs(action-button): made suggested edits

Co-authored-by: Najika Halsema Yoo <44980010+najikahalsema@users.noreply.github.com>

packages/action-button/README.md

@@ -581,7 +581,7 @@ With the application of the `toggles` attribute, the button will self manage its
 
 #### Include a label
 
-A button is required to have either a visible text label or `label` attribute on an `<sp-button>`
+A button is required to have either a visible text label or a `label` attribute on either the `<sp-button>` itself,
 or on an `<sp-icon*>` element child.
 
 #### Don't override color