Comment 18 for bug 1573052

It's not a problem and there is nothing to fix here.
This message is just to inform you that a module for reviews&ratings has failed to load. This would be an issue, but since Ubuntu is using a different module for the exact same feature, which disables the other one (that failed to load), there is no issue here at all.
This is resolved anyway in the next gnome-software, so the only thing you need to do is wait.
You can just ignore the message, as it isn't indicating any issue on Ubuntu.