style(tests): 统一事件测试中的lambda表达式格式

- 在EasyEvent_UnRegister_Should_Remove_Handler方法中将lambda表达式改为块状格式
- 在OrEventTests测试中将lambda表达式改为块状格式
- 保持代码风格一致性，所有lambda表达式都使用大括号包围

GFramework.Core.Tests/events/EventTests.cs

@@ -45,7 +45,7 @@ public class EventTests
     public void EasyEvent_UnRegister_Should_Remove_Handler()
     {
         var count = 0;
-        var handler = () => count++;
+        var handler = () => { count++; };
 
         _easyEvent.Register(handler);
         _easyEvent.Trigger();

GFramework.Core.Tests/events/OrEventTests.cs

@@ -88,7 +88,7 @@ public class OrEventTests
         var orEvent = new OrEvent();
 
         var count = 0;
-        var handler = () => count++;
+        var handler = () => { count++; };
 
         orEvent.Register(handler);
         orEvent.Or(@event);