React to logging changes

src/Microsoft.Net.Http.Server/LogHelper.cs

@@ -89,7 +89,7 @@ namespace Microsoft.Net.Http.Server
 
         private class NullLogger : ILogger
         {
-            public IDisposable BeginScopeImpl(object state)
+            public IDisposable BeginScope<TState>(TState state)
             {
                 return new NullDispose();
             }