Replace pydocstyle with Ruff (backport #692)

[mergify]

Pydocstyle was deprecated in favor of Ruff. Ruff has the exact same lints via the D ruleset.

As before, we only run the doc checks on source code and not tests.

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This is an automatic backport of pull request #692 done by Mergify.

[mergify]

Cherry-pick of 0415fc6 has failed:

On branch mergify/bp/stable/0.9/pr-692
Your branch is up to date with 'origin/stable/0.9'.

You are currently cherry-picking commit 0415fc6.
  (fix conflicts and run "git cherry-pick --continue")
  (use "git cherry-pick --skip" to skip this patch)
  (use "git cherry-pick --abort" to cancel the cherry-pick operation)

Changes to be committed:
	modified:   docs/conf.py
	modified:   qiskit_addon_cutting/__init__.py
	modified:   qiskit_addon_cutting/cut_finding/cutting_actions.py
	modified:   qiskit_addon_cutting/cut_finding/lo_cuts_optimizer.py
	modified:   qiskit_addon_cutting/cutting_decomposition.py
	modified:   qiskit_addon_cutting/cutting_experiments.py
	modified:   qiskit_addon_cutting/cutting_reconstruction.py
	modified:   qiskit_addon_cutting/qpd/decompose.py
	modified:   qiskit_addon_cutting/qpd/decompositions.py
	modified:   qiskit_addon_cutting/qpd/instructions/qpd_gate.py
	modified:   qiskit_addon_cutting/qpd/qpd_basis.py
	modified:   qiskit_addon_cutting/qpd/weights.py
	modified:   qiskit_addon_cutting/utils/__init__.py
	modified:   qiskit_addon_cutting/utils/bitwise.py
	modified:   qiskit_addon_cutting/utils/iteration.py
	modified:   qiskit_addon_cutting/utils/observable_grouping.py
	modified:   qiskit_addon_cutting/utils/simulation.py
	modified:   qiskit_addon_cutting/utils/transforms.py
	modified:   qiskit_addon_cutting/utils/transpiler_passes.py
	modified:   tox.ini

Unmerged paths:
  (use "git add <file>..." to mark resolution)
	both modified:   pyproject.toml

To fix up this pull request, you can check it out locally. See documentation: https://docs.github.com/en/pull-requests/collaborating-with-pull-requests/reviewing-changes-in-pull-requests/checking-out-pull-requests-locally

[coveralls]

Pull Request Test Coverage Report for Build 11504884065

Details

• 0 of 0 changed or added relevant lines in 0 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage remained the same at 100.0%

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Totals
Change from base Build 11504851603:	0.0%
Covered Lines:	2330
Relevant Lines:	2330

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💛 - Coveralls

[Eric-Arellano]

FYI @garrison I realized we don't need this cherry-picked after all. The new approach I'm taking for the API docs avoids the problem.

But doesn't hurt to cherry-pick