Remove unnecessary hop (#2136)

src/Microsoft.AspNetCore.SignalR.Client.Core/HubConnection.cs

@@ -86,6 +86,7 @@ namespace Microsoft.AspNetCore.SignalR.Client
             }
         }
 
+        // If the registered callback blocks it can cause the client to stop receiving messages. If you need to block, get off the current thread first.
         public IDisposable On(string methodName, Type[] parameterTypes, Func<object[], object, Task> handler, object state)
         {
             Log.RegisteringHandler(_logger, methodName);
@@ -443,9 +444,6 @@ namespace Microsoft.AspNetCore.SignalR.Client
 
         private async Task DispatchInvocationAsync(InvocationMessage invocation)
         {
-            // Make sure we get off the main event loop before we dispatch into user code
-            await AwaitableThreadPool.Yield();
-
             // Find the handler
             if (!_handlers.TryGetValue(invocation.Target, out var invocationHandlerList))
             {