扫描音乐前清空数据库，以防止重复

src/main/java/com/yutou/nas/Services/impl/MusicToolsServiceImpl.java

@@ -61,10 +61,11 @@ public class MusicToolsServiceImpl implements IMusicToolsService {
         new Thread(() -> {
             long startTime = System.currentTimeMillis();
             QQBotManager.getInstance().sendMessage("开始扫描音乐夹");
+            musicDataDao.truncate();
             isScan = true;
             scan(new File(musicPath));
             isScan = false;
-            com.yutou.nas.utils.Log.i("扫描完成");
+            Log.i("扫描完成");
             QQBotManager.getInstance().sendMessage("音乐扫描完成,共" + getLength() + "首歌,耗时:"
                     + (System.currentTimeMillis() - startTime));
         }).start();