[css-inline] Drop before-edge/after-edge as they seem to not be used in SVG and therefore aren't needed here.

Author: fantasai

css-inline/Overview.bs

@@ -185,8 +185,8 @@ Alignment Point: 'alignment-baseline' longhand</h4>
 	SVG implementations <em>may</em> support the following aliases
 	in order to support legacy content:
 	<pre dfn-for=alignment-baseline dfn-type=value>
-		<dfn>before-edge</dfn> | <dfn>text-before-edge</dfn> = ''alignment-baseline/text-top''
-		<dfn>after-edge</dfn> | <dfn>text-after-edge</dfn> = ''alignment-baseline/text-bottom''
+		<dfn>text-before-edge</dfn> = ''alignment-baseline/text-top''
+		<dfn>text-after-edge</dfn> = ''alignment-baseline/text-bottom''
 	</pre>
 	These values are not allowed in the 'vertical-align' shorthand.