Enable poetry tooling in pyproject.toml

[fleimgruber]

Is your feature request related to a problem? Please describe. As a developer installing the pandera dev environment I want to use poetry.

Describe the solution you'd like Translate the relevant sections of setup.py to pyproject.toml.

Describe alternatives you've considered

Additional context

[fleimgruber]

See #849.

[cosmicBboy]

See discussion in #849: basically this issue is blocked by pyproject.toml and poetry having better compatibility with setuptools.