[css-display-1] Remove excess parens.

Author: fantasai

css-display-3/Overview.bs

@@ -75,7 +75,7 @@ Introduction</h2>
 	of <dfn id="elements" oldids="css-element" export for=CSS lt="element">elements</dfn>
 	and <dfn id="text-nodes" oldids="css-text-node" export for=CSS lt="text node">text nodes</dfn>,
 	and renders it onto a <a href="https://www.w3.org/TR/CSS2/intro.html#canvas">canvas</a>
-	(such as your screen, a piece of paper, or an audio stream).
+	such as your screen, a piece of paper, or an audio stream.
 	(Some source documents start from more complex trees,
 	such as the DOM,
 	which can have comment nodes