refactor: remove an unnecessary argument

Co-authored-by: 沈星繁 <ikesnowy@outlook.com>

Author: cnblogs-dudu

test/Cnblogs.Architecture.IntegrationTestProject/Program.cs

@@ -33,7 +33,7 @@
 
 app.MapControllers();
 
-app.Subscribe<TestIntegrationEvent>(appName);
+app.Subscribe<TestIntegrationEvent>();
 
 var apis = app.NewVersionedApi();
 var v1 = apis.MapGroup("/api/v{version:apiVersion}").HasApiVersion(1);