Asp.net core 为什么文件在.NET核心主机中打开？

我刚刚从.NET Core 2.2升级到.NET Core 3.0

我有一个关于我的主项目的XUnitTest项目

重建时，我得到以下错误：

Could not copy "obj\Debug\netcoreapp3.0\XXX.dll" to "bin\Debug\netcoreapp3.0\XXX.dll". 
Exceeded retry count of 10. Failed. The file is locked by: ".NET Core Host (2016)"  


Unable to copy file "obj\Debug\netcoreapp3.0\XXX.dll" to "bin\Debug\netcoreapp3.0\XXX.dll". 
The process cannot access the file 'bin\Debug\netcoreapp3.0\Customer.Service.Tests.dll' because it is being used by another process.    

我还尝试手动删除bin文件夹，重新启动VS 2019。 “有效”的唯一方法是删除引用并重新启动计算机（win10）

为什么文件在.NET Core主机（2016）中打开？

问题在于招摇过市（swashback.AspNetCore） Swashback.AspNetCore 4.0.1不支持.NET Core 3.0

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版本5.0.0-rc3确实如此。

您是如何发现Swashback.AspNetCore是您的问题的原因的？