TT#158252 GET /api/subscriberpreferences fix ambiguous id

* distinct alias name was missing in the prefetch structure

Change-Id: I3a306160d96faa8a46bc8ae386d0c71f7d6cc59c

lib/NGCP/Panel/Utils/Preferences.pm

@@ -166,7 +166,7 @@ sub prepare_resource {
     $prefs = $prefs->search({
     }, {
         prefetch => 'attribute',
-        order_by => { '-asc' => 'id' },
+        order_by => { '-asc' => 'me.id' },
     });
 
     my $resource;