[css-text-3] Expand section title

Author: frivoal

css-text-3/Overview.bs

@@ -1278,7 +1278,7 @@ Order of Operations</h4>
     for details on wrapping behavior.
 
 <h2 id="white-space-processing">
-  White Space Processing Details</h2>
+  White Space Processing &amp; Control Characters</h2>
 
     The source text of a document often contains formatting
     that is not relevant to the final rendering: for example,