[css-lists] Fix example. Fixes #4031.

Author: tabatkins

css-lists-3/Overview.bs

@@ -343,7 +343,7 @@ Text-based Markers: the 'list-style-type' property</h3>
 			/* Sets all ordered lists to use the upper-roman counter-style
 			   (defined in the Counter Styles specification [[CSS-COUNTER-STYLES]]) */
 
-			ul { list-style-type: symbols(repeating '○' '●'); }
+			ul { list-style-type: symbols(cyclic '○' '●'); }
 			/* Sets all unordered list items to alternate between empty and
 			   filled circles for their markers. */