Remove duplication in comment

Author: 06b

sanitize.css

@@ -31,7 +31,7 @@
  * 2. Add the default cursor in all browsers (opinionated).
  * 3. Prevent adjustments of font size after orientation changes in
  *    IE on Windows Phone and in iOS.
- * 4. Breaks words to prevent prevent overflow in all browsers (opinionated).
+ * 4. Breaks words to prevent overflow in all browsers (opinionated).
  */
 
 html {