[css-syntax] Clarify an example: semicolon is not part of the declaration.

Author: SimonSapin

css-syntax/Overview.bs

@@ -71,7 +71,7 @@ Description of CSS's Syntax</h2>
 		which, if the source document is HTML,
 		selects any <code>&lt;a></code> elements that are children of a <code>&lt;p></code> element.
 
-		"<code>color: blue;</code>" is a declaration specifying that,
+		"<code>color: blue</code>" is a declaration specifying that,
 		for the elements that match the selector,
 		their 'color' property should have the value ''blue''.
 		Similarly, their 'text-decoration' property should have the value ''underline''.