test(Sass): remove ITestOutputHelper parameter (#7110)

Author: ArgoZhang

test/UniTest.Sass/VariableTest.cs

@@ -1,4 +1,4 @@
-// Licensed to the .NET Foundation under one or more agreements.
+// Licensed to the .NET Foundation under one or more agreements.
 // The .NET Foundation licenses this file to you under the Apache 2.0 License
 // See the LICENSE file in the project root for more information.
 // Maintainer: Argo Zhang([email protected]) Website: https://www.blazor.zone
@@ -7,7 +7,7 @@
 
 namespace UniTest.Sass;
 
-public partial class VariableTest(ITestOutputHelper testOutputHelper)
+public partial class VariableTest
 {
     [Fact]
     public void Variable_Ok()