In NamedArgumentTests - wrap Console.SetOut in a helper function that

will override the console before test and reset it after test.
Fixes #28667

Author: Robert Matusewicz

src/Microsoft.CSharp/tests/Helpers.cs

@@ -0,0 +1,25 @@
+using System;
+using System.IO;
+
+namespace Microsoft.CSharp.RuntimeBinder.Tests
+{
+    public static class Helpers
+    {
+        public static void OverrideConsoleAndRun(Action<StringWriter> command)
+        {
+            TextWriter savedOut = Console.Out;
+            try
+            {
+                using (var stringWriter = new StringWriter())
+                {
+                    Console.SetOut(stringWriter);
+                    command(stringWriter);
+                }
+            }
+            finally
+            {
+                Console.SetOut(savedOut);
+            }
+        }
+    }
+}

src/Microsoft.CSharp/tests/Microsoft.CSharp.Tests.csproj

@@ -16,6 +16,7 @@
     <Compile Include="BindingErrors.cs" />
     <Compile Include="EnumUnaryOperationTests.cs" />
     <Compile Include="ExplicitConversionTests.cs" />
+    <Compile Include="Helpers.cs" />
     <Compile Include="ImplicitConversionTests.cs" />
     <Compile Include="CSharpArgumentInfoTests.cs" />
     <Compile Include="DefaultParameterTests.cs" />
@@ -36,5 +37,8 @@
   <ItemGroup Condition="'$(TargetGroup)' == 'netcoreapp'">
     <Compile Include="AccessTests.netcoreapp.cs" />
   </ItemGroup>
+  <ItemGroup>
+    <Service Include="{82A7F48D-3B50-4B1E-B82E-3ADA8210C358}" />
+  </ItemGroup>
   <Import Project="$([MSBuild]::GetDirectoryNameOfFileAbove($(MSBuildThisFileDirectory), dir.targets))\dir.targets" />
-</Project>
+</Project>