Here's an example of a skipped test that seems to fail.  I think it's intermittent and this occurrence was on Windows:

[2020/08/12 20:38:09.550] test_encrypt07.test_encrypt07.test_salvage_process_empty ... skipped 'extension "encryptors/rotn" not built'
...
[2020/08/12 20:38:25.122] test_encrypt07.test_encrypt07.test_salvage_process_empty: 0.00 seconds
[2020/08/12 20:38:25.122] ERROR in test_encrypt07.test_encrypt07.test_salvage_process_empty

I don't know why it thinks it failed or how to figure that out. But perhaps we should always suppress showing something is an error if that test was skipped. This could happen in wttest.WiredTigerTestCase.tearDown.  Is it easy to tell if a function is marked as skipped, or do we have to track on our own when something is skipped?

If this happens with any frequency, it would be worth the effort.