feat：优化oss下载桶名获取

lib/core/services/download_service/impl/oss_download_impl.dart

@@ -126,7 +126,8 @@ class OSSDownloadImpl implements DownloadService {
   /// 获取oss bucketName
   String getOssBucketName() {
     if (baseUrl.contains("gateway.devclx.cn") ||
-        baseUrl.contains("gateway.testclx.cn")) {
+        baseUrl.contains("gateway.testclx.cn") ||
+        baseUrl.contains("gateway.preclx.cn")) {
       return "clx-dev";
     } else {
       return "clx-prod";