pyproject.toml, ruff, Python 3.10, update CI

[hagenw]

This modernizes the Python infrastructure of the project:

• Replace setup.cfg by pyproject.toml and update setup.py to focus only on dynamic package data selection
• Replace PEP8 checking in pre-commit with flake8 by ruff
• Add checking for common spelling errors with codespell in pre-commit
• Use Python 3.10 as default
• Update deprecated CI Actions