Fix unit test failure

The unit tests which depend on table formatting need to enable that
feature before running.

Author: jaredpar

src/Microsoft.DotNet.CodeFormatting.Tests/Rules/CombinationTest.cs

@@ -13,7 +13,7 @@ namespace Microsoft.DotNet.CodeFormatting.Tests
     /// <summary>
     /// A test which runs all rules on a given piece of code 
     /// </summary>
-    public sealed class CombinationTest : CodeFormattingTestBase
+    public sealed class CombinationTest : CodeFormattingTestBase, IDisposable
     {
         private static FormattingEngineImplementation s_formattingEngine;
 
@@ -25,10 +25,16 @@ static CombinationTest()
         public CombinationTest()
         {
             s_formattingEngine.CopyrightHeader = ImmutableArray.Create("// header");
+            s_formattingEngine.AllowTables = true;
             s_formattingEngine.FormatLogger = new EmptyFormatLogger();
             s_formattingEngine.PreprocessorConfigurations = ImmutableArray<string[]>.Empty;
         }
 
+        public void Dispose()
+        {
+            s_formattingEngine.AllowTables = false;
+        }
+
         protected override async Task<Document> RewriteDocumentAsync(Document document)
         {
             var solution = await s_formattingEngine.FormatCoreAsync(