Can somebody point me to the right direction on how to make this sample asp.net core web api app work in github spaces?

codespace:https://bookish-space-chainsaw-4jgw4575jvvhqg5g.github.dev/
github: https://github.com/xmione/Codespaces.API

I can build and run it using dotnet build and dotnet run commands but it gives me HTTP ERROR 404 when I try to browse it.

Hope someone can help me. Thanks in advance.