BUG with ProcessPool when scheduled function raise BaseException

[sergeykk]

In the following minimal snippet, f.result() hangs when scheduled function raises BaseException() . It works fine with concurrent.futures ProcessPoolExecutor

def test_pebble_exceptions():
    import pebble

    executor = pebble.ThreadPool()

    def foo():
        raise BaseException()

    try:
        f = executor.schedule(foo)
        f.result()
    except BaseException as e:
        assert isinstance(e, BaseException)

[noxdafox]

Issue fixed in release 5.0.6.