Fix the poetry support. Added a lockfile while setting up the virtual environments. This is specially important when using the tools as a pre-commit hook since on a clean system, we just one on of the invocations to setup the virtual environment, not all concurrent invocations.
0.20.3
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No significant changes.
0.20.2
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No significant changes.
0.20.1
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Added poetry as an extra, ie, `python -m pip install python-tools-scripts[poetry]`. Do note however that, if `poetry` is in path, the extra does not need to be provided.