[css-shapes-1] Missing comma between shape() parameters (#12280)

Author: cdoublev

css-shapes-1/Overview.bs

@@ -389,7 +389,7 @@ Supported Shapes</h3>
 
 		<<shape()>> = shape(
 			<<'fill-rule'>>?
-			from <<position>>
+			from <<position>> ,
 			<<shape-command>>#
 		)
 	</pre>