[css-text] Update comment about test coverage

Part of w3c#9511

Author: frivoal

css-text-4/Overview.bs

@@ -10425,7 +10425,7 @@ CJK Punctuation Spacing: the 'text-spacing-trim' property</h3>
 		* inheritance
 		* animation type
 		* applies to text
-		* tests for trim-auto, allow-end, auto values"></wpt>
+		* tests for trim-auto, trim-start, normal, auto values"></wpt>
 
 	<pre class="propdef">
 	Name: text-spacing-trim