[naot][android] Threading UnitTest failure

I see this failure in ci (but I can't repro it locally):

```
10-30 18:52:01.296 11767 11787 I DOTNET : ===== Running test Threading.Run =====
10-30 18:52:01.296 11767 11787 I DOTNET : WaitSubsystemTests.DoubleSetOnEventWithTimedOutWaiterShouldNotStayInWaitersList
10-30 18:52:01.356 11767 11787 I DOTNET : WaitSubsystemTests.ManualResetEventTest
10-30 18:52:01.565 11767 11787 I DOTNET : WaitSubsystemTests.AutoResetEventTest
10-30 18:52:01.770 11767 11787 I DOTNET : WaitSubsystemTests.SemaphoreTest
10-30 18:52:01.983 11767 11787 I DOTNET : WaitSubsystemTests.MutexTest
10-30 18:52:01.983 11767 11787 I DOTNET : WaitSubsystemTests.WaitDurationTest
10-30 18:52:03.485 11767 11787 I DOTNET : TimersCreatedConcurrentlyOnDifferentThreadsAllFire
10-30 18:52:03.555 11767 11787 I DOTNET : ThreadPoolTests.RunProcessorCountItemsInParallel
10-30 18:52:03.556 11767 11787 I DOTNET : ThreadPoolTests.RunMoreThanMaxJobsMakesOneJobWaitForStarvationDetection
10-30 18:52:04.548 11767 11787 I DOTNET : ThreadPoolTests.ThreadPoolCanPickUpOneJobWhenThreadIsAvailable
10-30 18:52:20.917 1683 1683 E netmgr : Failed to open QEMU pipe 'qemud:network': Invalid argument
10-30 18:52:21.144 1687 1687 E wifi_forwarder: RemoteConnection failed to initialize: RemoteConnection failed to open pipe
10-30 18:52:32.982 1886 1900 D WificondControl: Scan result ready event
10-30 18:52:34.549 11767 11787 I DOTNET : Assertion failure - Assert.True
10-30 18:52:34.551 11767 11787 I DOTNET : AssertionFailureException: Exception of type 'AssertionFailureException' was thrown.
10-30 18:52:34.551 11767 11787 I DOTNET : at Assert.True(Boolean) + 0x3f
10-30 18:52:34.551 11767 11787 I DOTNET : at ThreadPoolTests.ThreadPoolCanPickUpOneJobWhenThreadIsAvailable() + 0x116
10-30 18:52:34.551 11767 11787 I DOTNET : at Threading.Run() + 0xae
10-30 18:52:34.551 11767 11787 I DOTNET : at Program.g__RunTest|0_0(Func`1, String) + 0x49
10-30 18:52:34.551 11767 11787 I DOTNET : ===== Test Threading.Run failed =====
```