减少重试获取vid文件次数为2次

lib/data_host/web/shell.dart

@@ -38,7 +38,7 @@ class _VidDataHostShell implements VidDataHostInterface {
       return await _platform.getVidFile(url);
     } catch (e) {
       logger.e('_VidDataHostShell load $times ex:', e);
-      if (times < 3) {
+      if (times < 2) {
         return await getVidFile(url, times: times++);
       }
       return null;