fixed test hang

Author: mikaelm12

src/Microsoft.AspNetCore.SignalR.Redis/RedisHubLifetimeManager.cs

@@ -190,6 +190,7 @@ public override Task InvokeGroupAsync(string groupName, string methodName, objec
                 throw new ArgumentNullException(nameof(groupName));
             }
 
+            //var message = new InvocationMessage(GetInvocationId(), nonBlocking: true, target: methodName, argumentBindingException: null, arguments: args);
             var message = new RedisExcludeClientsMessage(GetInvocationId(), nonBlocking: true, target: methodName, excludedIds: null, arguments: args);
 
             return PublishAsync(_channelNamePrefix + ".group." + groupName, message);
@@ -564,7 +565,7 @@ private Task SubscribeToGroup(string groupChannel, GroupData group)
                     var tasks = new List<Task>();
                     foreach (var groupConnection in group.Connections)
                     {
-                        if (message.ExcludedIds.Contains(groupConnection.ConnectionId))
+                        if (message.ExcludedIds?.Contains(groupConnection.ConnectionId) == true)
                         {
                             continue;
                         }