Use hyphen for underscore in publish-modal style

services/web/public/stylesheets/components/publish-modal.less

@@ -1,5 +1,5 @@
 .publish-guide .form-control,
 .publish-guide .form-control-box {
   width: 70%;
-  margin_bottom: 1.0ex;
+  margin-bottom: 1.0ex;
 }