Running local tests

[danodonovan]

While patching #17 I'm running into issues with the tox testing suite.

In particular, a simple $ tox execution produces errors like

__________________________________________________________________________________ ERROR collecting tests/test_plugin.py ___________________________________________________________________________________
ImportError while importing test module '/Users/dan/Code/tox-ltt/tests/test_plugin.py'.
Hint: make sure your test modules/packages have valid Python names.
Traceback:
../../.pyenv/versions/3.8.11/lib/python3.8/importlib/__init__.py:127: in import_module
    return _bootstrap._gcd_import(name[level:], package, level)
tests/test_plugin.py:5: in <module>
    from light_the_torch.computation_backend import CPUBackend
E   ModuleNotFoundError: No module named 'light_the_torch.computation_backend'

.. which I'm not surprised by as I can't see where light_the_torch is being installed or listed as a requirement. Edit: setup.cfg Do we expect the test suite to still run? (I not the CI hasn't run for 10 months). Thanks (and congratulations BTW 👶)