Convert TextOnlyComponent to Razor format

test/testapps/BasicTestApp/TextOnlyComponent.cs

@@ -1,16 +0,0 @@
-// Copyright (c) .NET Foundation. All rights reserved.
-// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
-
-using Microsoft.Blazor.Components;
-using Microsoft.Blazor.RenderTree;
-
-namespace BasicTestApp
-{
-    public class TextOnlyComponent : IComponent
-    {
-        public void BuildRenderTree(RenderTreeBuilder builder)
-        {
-            builder.AddText($"Hello from {nameof(TextOnlyComponent)}");
-        }
-    }
-}

test/testapps/BasicTestApp/TextOnlyComponent.cshtml

@@ -0,0 +1 @@
+Hello from TextOnlyComponent