dashboard: fix weird css comment

lessc@2.6.0 compile failed
lessc@2.6.1 compiled it fine but better safe than sorry

closes #438

circle/dashboard/static/dashboard/dashboard.less

@@ -284,7 +284,7 @@ a.hover-black {
 }
 
 .hover-black:hover {
-  color: black /*#d9534f*/;
+  color: black; /*#d9534f*/
   text-decoration: none;
 }