Delete unrelated test file from System.Console.Tests (#72033)

src/libraries/System.Console/tests/NegativeTesting.cs

-// Licensed to the .NET Foundation under one or more agreements.
-// The .NET Foundation licenses this file to you under the MIT license.
-
-using System;
-using System.IO;
-using Xunit;
-
-public class NegativeTesting
-{
-    [Fact]
-    public static void StreamNullTests()
-    {
-        Stream stream = Stream.Null;
-
-        Assert.Equal(0L, stream.Length);
-
-        Assert.Equal(0L, stream.Position);
-
-        stream.Position = 50L;
-        stream.SetLength(50L);
-        Assert.Equal(0L, stream.Length);
-
-        // Flushing a stream is fine.
-        stream.Flush();
-
-        //Read and write methods
-
-        Assert.Equal(0, stream.Read(null, 0, 1));
-        Assert.Equal(0, stream.Read(new byte[] { 0, 1 }, -1, 0));
-        Assert.Equal(0, stream.Read(new byte[] { 0, 1 }, 0, -1));
-        Assert.Equal(0, stream.Read(new byte[] { 0, 1 }, 0, 50));
-        Assert.Equal(0, stream.Read(new byte[] { 0, 1 }, 0, 2));
-
-        stream.Write(null, 0, 1);
-        stream.Write(new byte[] { 0, 1 }, -1, 0);
-        stream.Write(new byte[] { 0, 1 }, 0, -1);
-        stream.Write(new byte[] { 0, 1 }, 0, 50);
-
-        Assert.Equal(0L, stream.Seek(0L, SeekOrigin.Begin));
-
-        // Null stream even ignores Dispose.
-        stream.Dispose();
-
-        Assert.Equal(0, stream.Read(new byte[] { 0, 1 }, 0, 1));
-        stream.Write(new byte[] { 0, 1 }, 0, 1);
-        stream.Flush();
-    }
-}

src/libraries/System.Console/tests/System.Console.Tests.csproj

@@ -14,7 +14,6 @@
     <Compile Include="SetIn.cs" />
     <Compile Include="Color.cs" />
     <Compile Include="SetOut.cs" />
-    <Compile Include="NegativeTesting.cs" />
     <Compile Include="ConsoleEncoding.cs" />
     <Compile Include="SyncTextReader.cs" />
     <Compile Include="SyncTextWriter.cs" />