System.AggregateException : One or more errors occurred. (Timeout (00:00:09.9994528) while waiting for messages. Only received 0/1 messages that matched filter [Error when Message contains "Upstream producer failed with exception"])
---- Timeout (00:00:09.9994528) while waiting for messages. Only received 0/1 messages that matched filter [Error when Message contains "Upstream producer failed with exception"]

at System.Threading.Tasks.Task`1.GetResultCore(Boolean waitCompletionNotification)
   at Akka.TestKit.TestKitBase.WithinAsync[T](TimeSpan min, TimeSpan max, Func`1 function, String hint, Nullable`1 epsilonValue, CancellationToken cancellationToken) in /home/vsts/work/1/s/src/core/Akka.TestKit/TestKitBase_Within.cs:line 311
   at Akka.TestKit.TestKitBase.WithinAsync(TimeSpan max, Func`1 actionAsync, Nullable`1 epsilonValue, CancellationToken cancellationToken) in /home/vsts/work/1/s/src/core/Akka.TestKit/TestKitBase_Within.cs:line 63
   at Akka.Streams.Tests.Dsl.HubSpec.<MergeHub_must_keep_working_even_if_one_of_the_producers_fail>b__14_0() in /home/vsts/work/1/s/src/core/Akka.Streams.Tests/Dsl/HubSpec.cs:line 267
   at Akka.Streams.TestKit.Utils.<>c__DisplayClass5_0.<<AssertAllStagesStoppedAsync>b__0>d.MoveNext() in /home/vsts/work/1/s/src/core/Akka.Streams.TestKit/Utils.cs:line 59
--- End of stack trace from previous location ---
   at Akka.TestKit.Extensions.TaskExtensions.<>c__DisplayClass5_0`1.<<ShouldCompleteWithin>b__0>d.MoveNext()
--- End of stack trace from previous location ---
   at FluentAssertions.Specialized.GenericAsyncFunctionAssertions`1.CompleteWithinAsync(TimeSpan timeSpan, String because, Object[] becauseArgs)
   at Akka.TestKit.Extensions.TaskExtensions.ShouldCompleteWithin[T](Task`1 task, TimeSpan timeout, String because, Object[] becauseArgs)
   at Akka.Streams.TestKit.Utils.AssertAllStagesStoppedAsync[T](TestKitBase spec, Func`1 block, IMaterializer materializer, Nullable`1 timeout, CancellationToken cancellationToken)
   at Akka.Streams.TestKit.Utils.AssertAllStagesStoppedAsync(TestKitBase spec, Func`1 block, IMaterializer materializer, Nullable`1 timeout, CancellationToken cancellationToken) in /home/vsts/work/1/s/src/core/Akka.Streams.TestKit/Utils.cs:line 57
   at Akka.Streams.Tests.Dsl.HubSpec.MergeHub_must_keep_working_even_if_one_of_the_producers_fail() in /home/vsts/work/1/s/src/core/Akka.Streams.Tests/Dsl/HubSpec.cs:line 263
--- End of stack trace from previous location ---
----- Inner Stack Trace -----
   at Akka.TestKit.Xunit2.XunitAssertions.Fail(String format, Object[] args) in /home/vsts/work/1/s/src/contrib/testkits/Akka.TestKit.Xunit2/XunitAssertions.cs:line 26
   at Akka.TestKit.Internal.InternalEventFilterApplier.InterceptAsync[T](Func`1 func, ActorSystem system, Nullable`1 timeout, Nullable`1 expectedOccurrences, MatchedEventHandler matchedEventHandler, CancellationToken cancellationToken) in /home/vsts/work/1/s/src/core/Akka.TestKit/EventFilter/Internal/EventFilterApplier.cs:line 439
   at Akka.TestKit.Internal.InternalEventFilterApplier.InternalExpectAsync(Func`1 actionAsync, ActorSystem actorSystem, Int32 expectedCount, Nullable`1 timeout, CancellationToken cancellationToken) in /home/vsts/work/1/s/src/core/Akka.TestKit/EventFilter/Internal/EventFilterApplier.cs:line 505
   at Akka.TestKit.Internal.InternalEventFilterApplier.ExpectOneAsync(Func`1 action, CancellationToken cancellationToken) in /home/vsts/work/1/s/src/core/Akka.TestKit/EventFilter/Internal/EventFilterApplier.cs:line 67
   at Akka.Streams.Tests.Dsl.HubSpec.<>c__DisplayClass14_0.<<MergeHub_must_keep_working_even_if_one_of_the_producers_fail>b__1>d.MoveNext() in /home/vsts/work/1/s/src/core/Akka.Streams.Tests/Dsl/HubSpec.cs:line 269
--- End of stack trace from previous location ---
   at Akka.TestKit.TestKitBase.<>c__DisplayClass217_0.<<WithinAsync>b__0>d.MoveNext() in /home/vsts/work/1/s/src/core/Akka.TestKit/TestKitBase_Within.cs:line 68