处理批量导出知识时如果存在同名文件错误

src/Hotline.Application/Knowledge/KnowApplication.cs

@@ -202,7 +202,10 @@ namespace Hotline.Application.Knowledge
 
             foreach (var kvp in results)
             {
-                streamList.Add(kvp.Key, kvp.Value);
+                if (!streamList.ContainsKey(kvp.Key))
+                {
+                    streamList.Add(kvp.Key, kvp.Value);
+                }
             }
 
             return streamList;