Switch to Ruff tools, update pre-commit

[mwtoews]

The aims of this PR are to switch to faster/modern Ruff-based lint and formatting tools, and to update the pre-commit workflow. Details:

• Replace "black", "isort" and "flake8" with Ruff. Some of these rules are selected in pyproject.toml, and I think most others are enabled by default. But keep blacken-docs for now, with the black version updated.
• Remove unused configuration files (and references in MANIFEST.in)
• Remove deprecated fix-encoding-pragma which is replaced by pyupgrade/"UP" Ruff rule. Other changes from this rule are removing default "r" from open() statements
• Update sort-simple-yaml to look for any "config.yaml" file (there wasn't any grayskull/pypi/config.yaml file). The change from this sorts keys in grayskull/strategy/config.yaml

[marcelotrevisani]

Thanks for that, I wanted to move to use ruff but I was always forgetting about it.