Microsoft.Extensions.Http test failure on mono

[maryamariyan]

This issue tracks Http test failing on Mono:

Microsoft.Extensions.Http.DefaultHttpClientFactoryTest.Factory_CleanupCycle_DisposesLiveHandler

https://helix.dot.net/api/2019-06-17/jobs/c6ed46b1-0512-4f5d-b721-ecaaaa01dc59/workitems/Microsoft.Extensions.Http.Tests/console

Discovering: Microsoft.Extensions.Http.Tests (method display = ClassAndMethod, method display options = None)
  Discovered:  Microsoft.Extensions.Http.Tests (found 70 test cases)
  Starting:    Microsoft.Extensions.Http.Tests (parallel test collections = on, max threads = 2)
    Microsoft.Extensions.Http.DefaultHttpClientFactoryTest.Factory_CleanupCycle_DisposesLiveHandler [FAIL]
      Cleanup entry disposable
      Expected: True
      Actual:   False
      Stack Trace:
        /_/src/libraries/Microsoft.Extensions.Http/tests/DefaultHttpClientFactoryTest.cs(449,0): at Microsoft.Extensions.Http.DefaultHttpClientFactoryTest.Factory_CleanupCycle_DisposesLiveHandler()
        --- End of stack trace from previous location ---
  Finished:    Microsoft.Extensions.Http.Tests

[safern]

Added console output to description since the file links might expire.

[danmoseley]

@maryamariyan there is a label runtime-mono that is handy for mono specific issues

[danmoseley]

Likely relates to different GC behavior on Mono. Test says "depends on the GC and timing."

[jkotas]

Failed in #39717

[danmoseley]

@maryamariyan please fix or disable