保护性修复：音乐选择里tag为空时不展示空白区域

BFFramework/Classes/Stuckpoint/ViewModel/PQStuckPointViewModel.swift

@@ -64,7 +64,7 @@ public class PQStuckPointViewModel: NSObject {
             currtentX = currtentX + itemSpace + width
             attributesArray.append(attributes)
         }
-        return (attributesArray, currtentY + lineSpace + itemHeight)
+        return (attributesArray, attributesArray.count > 0 ? currtentY + lineSpace + itemHeight : 0)
     }
 
     /// 卡点音乐某个分类下列表