Net6.0 Minimal API projects without Startup, issue #3794 (#3814)

Fixes missing controllers in the specification when generating Net6.0 Minimal API projects using CLI/MSBuild

src/NSwag.Commands/HostApplication.cs

@@ -140,7 +140,13 @@ void OnEntryPointExit(Exception exception)
             try
             {
                 // Get the IServiceProvider from the host
+#if NET6_0
+                var assemblyName = assembly.GetName()?.FullName ?? string.Empty;
+                // We should set the application name to the startup assembly to avoid falling back to the entry assembly.
+                var services = ((IHost)factory(new[] { $"--{HostDefaults.ApplicationKey}={assemblyName}" })).Services;
+#else
                 var services = ((IHost)factory(Array.Empty<string>())).Services;
+#endif
 
                 // Wait for the application to start so that we know it's fully configured. This is important because
                 // we need the middleware pipeline to be configured before we access the ISwaggerProvider in
@@ -176,4 +182,4 @@ public void Dispose() { }
             public Task StopAsync(CancellationToken cancellationToken) => Task.CompletedTask;
         }
     }
-}
+}