Broken on Python 3.8

[douglas-raillard-arm]

Tests fail on Python 3.8:

================================================================================== short test summary info ==================================================================================
FAILED cloudpickle_generators/tests/test_cloudpickle_generators.py::test_simple_generator - TypeError: _save_generator() missing 1 required positional argument: 'gen'
FAILED cloudpickle_generators/tests/test_cloudpickle_generators.py::test_stack - TypeError: _save_generator() missing 1 required positional argument: 'gen'
FAILED cloudpickle_generators/tests/test_cloudpickle_generators.py::test_block_stack - TypeError: _save_generator() missing 1 required positional argument: 'gen'
FAILED cloudpickle_generators/tests/test_cloudpickle_generators.py::test_arguments - TypeError: _save_generator() missing 1 required positional argument: 'gen'
FAILED cloudpickle_generators/tests/test_cloudpickle_generators.py::test_exc_info - TypeError: _save_generator() missing 1 required positional argument: 'gen'
FAILED cloudpickle_generators/tests/test_cloudpickle_generators.py::test_closure - TypeError: _save_generator() missing 1 required positional argument: 'gen'
FAILED cloudpickle_generators/tests/test_cloudpickle_generators.py::test_freevars - TypeError: _save_generator() missing 1 required positional argument: 'gen'
FAILED cloudpickle_generators/tests/test_cloudpickle_generators.py::test_freevars_and_cellvars - TypeError: _save_generator() missing 1 required positional argument: 'gen'
FAILED cloudpickle_generators/tests/test_cloudpickle_generators.py::test_self_in_closure - TypeError: _save_generator() missing 1 required positional argument: 'gen'
FAILED cloudpickle_generators/tests/test_cloudpickle_generators.py::test_references_global - TypeError: _save_generator() missing 1 required positional argument: 'gen'
FAILED cloudpickle_generators/tests/test_cloudpickle_generators.py::test_fully_consumed - TypeError: _save_generator() missing 1 required positional argument: 'gen'
FAILED cloudpickle_generators/tests/test_cloudpickle_generators.py::test_running - TypeError: _save_generator() missing 1 required positional argument: 'gen'
FAILED cloudpickle_generators/tests/test_segfault.py::test_1 - TypeError: _save_generator() missing 1 required positional argument: 'gen'
FAILED cloudpickle_generators/tests/py35/test_coroutines.py::test_simple_coro - TypeError: _save_coroutine() missing 1 required positional argument: 'coro'
FAILED cloudpickle_generators/tests/py35/test_coroutines.py::test_stack - TypeError: _save_generator() missing 1 required positional argument: 'gen'
FAILED cloudpickle_generators/tests/py35/test_coroutines.py::test_arguments - TypeError: _save_coroutine() missing 1 required positional argument: 'coro'
FAILED cloudpickle_generators/tests/py35/test_coroutines.py::test_exc_info - TypeError: _save_coroutine() missing 1 required positional argument: 'coro'
FAILED cloudpickle_generators/tests/py35/test_coroutines.py::test_closure - TypeError: _save_coroutine() missing 1 required positional argument: 'coro'
FAILED cloudpickle_generators/tests/py35/test_coroutines.py::test_freevars - TypeError: _save_coroutine() missing 1 required positional argument: 'coro'
FAILED cloudpickle_generators/tests/py35/test_coroutines.py::test_freevars_and_cellvars - TypeError: _save_coroutine() missing 1 required positional argument: 'coro'
FAILED cloudpickle_generators/tests/py35/test_coroutines.py::test_self_in_closure - TypeError: _save_coroutine() missing 1 required positional argument: 'coro'
FAILED cloudpickle_generators/tests/py35/test_coroutines.py::test_references_global - TypeError: _save_coroutine() missing 1 required positional argument: 'coro'
FAILED cloudpickle_generators/tests/py35/test_coroutines.py::test_fully_consumed - TypeError: _save_coroutine() missing 1 required positional argument: 'coro'
FAILED cloudpickle_generators/tests/py35/test_coroutines.py::test_namespace_1 - TypeError: _save_coroutine() missing 1 required positional argument: 'coro'
FAILED cloudpickle_generators/tests/py35/test_coroutines.py::test_namespace_2 - TypeError: _save_coroutine() missing 1 required positional argument: 'coro'
FAILED cloudpickle_generators/tests/py36/test_async_generators.py::test_async_generator_0 - TypeError: _save_async_generator() missing 1 required positional argument: 'asyncgen'
FAILED cloudpickle_generators/tests/py36/test_async_generators.py::test_async_generator_1 - TypeError: _save_async_generator() missing 1 required positional argument: 'asyncgen'
FAILED cloudpickle_generators/tests/py36/test_async_generators.py::test_async_generator_2 - TypeError: _save_async_generator() missing 1 required positional argument: 'asyncgen'
=============================================================================== 28 failed, 3 passed in 0.60s ================================================================================
sys:1: RuntimeWarning: coroutine 'test_freevars_and_cellvars.<locals>.g.<locals>.f' was never awaited
RuntimeWarning: Enable tracemalloc to get the object allocation traceback
sys:1: RuntimeWarning: coroutine 'test_self_in_closure.<locals>.f' was never awaited
RuntimeWarning: Enable tracemalloc to get the object allocation traceback

There seems to have been an API change inside cloudpickle that broke cloudpickle-generators