[css-writing-modes-3] Add back dropped change

Author: fantasai

css-writing-modes-3/Overview.bs

@@ -2542,6 +2542,9 @@ Privacy and Security Considerations {#priv-sec}
       (<a href="https://github.com/w3c/csswg-drafts/issues/3779">Issue 3779</a>)
     <li>Updated “Applies to” line for 'text-combine-upright' to mention text
       (since certain effects like ''display: contents'' can strip the box itself).
+    <li>
+      Clarified that the [=central baseline=] is the [=ideographic central baseline=].
+      (<a href="https://github.com/w3c/csswg-drafts/issues/5177">Issue 5177</a>)
     <li>Reshuffled text in the [[#intro]] and improved cross-linking.
   </ul>