Fix pre-commit TOML formatting and flake8 warning

[vlad-perevezentsev]

Apply the pretty-format-toml hook to pyproject.toml and silence the flake8 B018 warning in dpnp.split

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[github-actions]

View rendered docs @ https://intelpython.github.io/dpnp/pull/3075/index.html

[github-actions]

Array API standard conformance tests for dpnp=0.21.0dev8=py314ha0e2e8e_13 ran successfully.
Passed: 1376
Failed: 0
Skipped: 6