bugfix:集成测试下获取种子数据报错

Api/Ewide.EntityFramework.Core/DbContexts/DefaultDbContext.cs

@@ -166,6 +166,8 @@ namespace Ewide.EntityFramework.Core
         protected override void OnModelCreating(ModelBuilder modelBuilder)
         {
             base.OnModelCreating(modelBuilder);
+            if (App.HostEnvironment.EnvironmentName == "Testing") return;
+            //集成测试下面代码会报错
             XmlSerializerUtil xmlHandler = new XmlSerializerUtil();
             Dictionary<Type, object> dic = xmlHandler.ReaderALL();
             foreach (KeyValuePair<Type, object> item in dic)