Fixed: Include preferred size in quality definition reset

(cherry picked from commit 8e925ac76d2f46cf5fef1ea62a20ae5e85d3000e)

src/NzbDrone.Core/Qualities/QualityDefinitionService.cs

@@ -121,6 +121,7 @@ namespace NzbDrone.Core.Qualities
 
                 existing.MinSize = definition.MinSize;
                 existing.MaxSize = definition.MaxSize;
+                existing.PreferredSize = definition.PreferredSize;
                 existing.Title = message.ResetTitles ? definition.Title : existing.Title;
 
                 updateList.Add(existing);