Fix build

Author: NikolayPianikov

CSharpInteractive.Tests/UsageScenarios/DotNetSlnAddScenario.cs

@@ -37,6 +37,8 @@ public void Run()
             .WithForce(true)
             .Run().EnsureSuccess();
 
+        new CommandLine("dir").Run();
+
         new DotNetSlnAdd()
             .WithSolution("MySolution.sln")
             .AddProjects(