Ad tests, fix issue where profile not found isn't an error

TestAssets/TestProjects/MSBuildTestAppWithLaunchSettingsWithoutDefault/Program.cs

@@ -0,0 +1,26 @@
+// Copyright (c) .NET Foundation and contributors. All rights reserved.
+// Licensed under the MIT license. See LICENSE file in the project root for full license information.
+
+using System;
+
+namespace MSBuildTestApp
+{
+    public class Program
+    {
+        public static void Main(string[] args)
+        {
+            if (args.Length > 0)
+            {
+                Console.WriteLine("echo args:" + string.Join(";", args));
+            }
+            string message = Environment.GetEnvironmentVariable("Message");
+
+            if (string.IsNullOrEmpty(message))
+            {
+                message = "(NO MESSAGE)";
+            }
+
+            Console.WriteLine(message);
+        }
+    }
+}