Add additional test cases (#125)

Test-only changes for code coverage.  Please review the comment and I'll include the changes in the next iteration.

* Add more tests

* Add some more additional test cases

test/Microsoft.SqlTools.ServiceLayer.TestDriver/Tests/ConnectionTests.cs

@@ -0,0 +1,45 @@
+//
+// Copyright (c) Microsoft. All rights reserved.
+// Licensed under the MIT license. See LICENSE file in the project root for full license information.
+//
+
+using System;
+using System.Collections.Generic;
+using System.Diagnostics;
+using System.Linq;
+using System.Threading;
+using System.Threading.Tasks;
+using Microsoft.SqlTools.ServiceLayer.LanguageServices.Contracts;
+using Microsoft.SqlTools.ServiceLayer.TestDriver.Utility;
+using Microsoft.SqlTools.ServiceLayer.Workspace.Contracts;
+using Xunit;
+
+namespace Microsoft.SqlTools.ServiceLayer.TestDriver.Tests
+{
+    /// <summary>
+    /// Language Service end-to-end integration tests
+    /// </summary>
+    public class ConnectionTests : TestBase
+    {
+        /// <summary>
+        /// Try to connect with invalid credentials
+        /// </summary>
+        //[Fact]
+        public async Task InvalidConnection()
+        {
+            try
+            {            
+                string ownerUri = System.IO.Path.GetTempFileName();
+                bool connected = await Connect(ownerUri, ConnectionTestUtils.InvalidConnection);
+                Assert.False(connected, "Invalid connection is failed to connect");
+
+                await Disconnect(ownerUri);
+            }
+            finally
+            {
+                WaitForExit();
+            }
+        }
+
+    }
+}