bug#39869: python-orator build fails

[Maxim Cournoyer <maxim.cournoyer@gmail.com>]

Build log extract:

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======================================================================
ERROR: orator.commands.migrations (unittest.loader._FailedTest)
----------------------------------------------------------------------
ImportError: Failed to import test module: orator.commands.migrations
Traceback (most recent call last):
  File "/gnu/store/78w7y0lxar70j512iqw8x3nimzj10yga-python-3.7.4/lib/python3.7/unittest/loader.py", line 470, in _find_test_path
    package = self._get_module_from_name(name)
  File "/gnu/store/78w7y0lxar70j512iqw8x3nimzj10yga-python-3.7.4/lib/python3.7/unittest/loader.py", line 377, in _get_module_from_name
    __import__(name)
  File "/tmp/guix-build-python-orator-0.9.7.drv-0/orator-0.9.7/orator/commands/migrations/__init__.py", line 3, in <module>
    from .install_command import InstallCommand
  File "/tmp/guix-build-python-orator-0.9.7.drv-0/orator-0.9.7/orator/commands/migrations/install_command.py", line 4, in <module>
    from .base_command import BaseCommand
  File "/tmp/guix-build-python-orator-0.9.7.drv-0/orator-0.9.7/orator/commands/migrations/base_command.py", line 5, in <module>
    from ..command import Command
  File "/tmp/guix-build-python-orator-0.9.7.drv-0/orator-0.9.7/orator/commands/command.py", line 4, in <module>
    from cleo import Command as BaseCommand, InputOption, ListInput
ImportError: cannot import name 'InputOption' from 'cleo' (/gnu/store/iwhbrhr49wf6gxhxlripjf4ij0y41r3x-python-cleo-0.7.6/lib/python3.7/site-packages/cleo/__init__.py)


======================================================================
ERROR: orator.commands.seeds (unittest.loader._FailedTest)
----------------------------------------------------------------------
ImportError: Failed to import test module: orator.commands.seeds
Traceback (most recent call last):
  File "/gnu/store/78w7y0lxar70j512iqw8x3nimzj10yga-python-3.7.4/lib/python3.7/unittest/loader.py", line 470, in _find_test_path
    package = self._get_module_from_name(name)
  File "/gnu/store/78w7y0lxar70j512iqw8x3nimzj10yga-python-3.7.4/lib/python3.7/unittest/loader.py", line 377, in _get_module_from_name
    __import__(name)
  File "/tmp/guix-build-python-orator-0.9.7.drv-0/orator-0.9.7/orator/commands/seeds/__init__.py", line 3, in <module>
    from .make_command import SeedersMakeCommand
  File "/tmp/guix-build-python-orator-0.9.7.drv-0/orator-0.9.7/orator/commands/seeds/make_command.py", line 7, in <module>
    from .base_command import BaseCommand
  File "/tmp/guix-build-python-orator-0.9.7.drv-0/orator-0.9.7/orator/commands/seeds/base_command.py", line 4, in <module>
    from ..command import Command
  File "/tmp/guix-build-python-orator-0.9.7.drv-0/orator-0.9.7/orator/commands/command.py", line 4, in <module>
    from cleo import Command as BaseCommand, InputOption, ListInput
ImportError: cannot import name 'InputOption' from 'cleo' (/gnu/store/iwhbrhr49wf6gxhxlripjf4ij0y41r3x-python-cleo-0.7.6/lib/python3.7/site-packages/cleo/__init__.py)


----------------------------------------------------------------------
Ran 6 tests in 0.001s

FAILED (errors=6)
Test failed: <unittest.runner.TextTestResult run=6 errors=6 failures=0>
error: Test failed: <unittest.runner.TextTestResult run=6 errors=6 failures=0>
command "python" "-c" "import setuptools, tokenize;__file__='setup.py';f=getattr(tokenize, 'open', open)(__file__);code=f.read().replace('\\r\\n', '\\n');f.close();exec(compile(code, __file__, 'exec'))" "test" failed with status 1
--8<---------------cut here---------------end--------------->8---

Tested on master c1febbbf94ee794d7a97dbde12102634f2b13529.