Upgrade NUnit infra

Author: andrewvk

CodeJam.Main.Tests/CodeJam.Main.Tests.csproj

@@ -16,8 +16,8 @@
 	</ItemGroup>
 	<ItemGroup Condition=" '$(TargetFramework)' != 'net20' AND '$(TargetFramework)' != 'netcoreapp1.1' ">
 		<PackageReference Include="NUnit" Version="3.12.0" />
-		<PackageReference Include="NUnit3TestAdapter" Version="3.17.0" />
-		<PackageReference Include="Microsoft.NET.Test.Sdk" Version="16.8.0" />
+		<PackageReference Include="NUnit3TestAdapter" Version="4.2.1" />
+		<PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.2.0" />
 	</ItemGroup>
 	<!-- #endregion -->