[css-align] flex-end without semicolon

The production rules for self-position and content-position
previously ended with `| flex-end;`

The semicolon is not needed.

Author: ericwilligers

css-align-3/Overview.bs

@@ -359,15 +359,15 @@ Positional Alignment: the ''center'', ''start'', ''end'', ''self-start'', ''self
 			(to specify default values for 'justify-self' and 'align-self').
 			<pre class='prod'>
 				<dfn>&lt;self-position></dfn> = center | start | end | self-start | self-end |
-								flex-start | flex-end;
+								flex-start | flex-end
 			</pre>
 		<dt><<content-position>>
 		<dd>
 			This set is used by 'justify-content' and 'align-content'
 			to align the box's contents within itself.
 
 			<pre class='prod'>
-				<dfn>&lt;content-position></dfn> = center | start | end | flex-start | flex-end;
+				<dfn>&lt;content-position></dfn> = center | start | end | flex-start | flex-end
 			</pre>
 	</dl>