[css-contain-1] Update Changes section

Author: frivoal

css-contain-1/Overview.bs

@@ -894,7 +894,8 @@ This appendix is <em>informative</em>.
 		Editorial tweaks:
 		<ul>
 			<li>
-				phrasing improvement in [[#containment-size]] to highlight that "sizing" includes "intrinsic sizing"
+				phrasing improvements in [[#containment-size]] to highlight that "sizing" includes "intrinsic sizing",
+				and improve the general legibility of some sentence.
 
 			<li>
 				phrasing improvement in [[#containment-paint]] to use established terminology rather than ad-hoc wording with the same intended meaning