Add pre-commit hook and GHA workflow to apply `black` linter to Python files

[jhlegarreta]

Description

Add a pre-commit hook and GHA workflow to apply the black linter to Python files.

Expected coding style

ITK contains numerous Python files: by applying a pre-commit hook and GHA workflow to apply the black linter to such files would improve readability across such files by standardizing their style.

Actual coding style

No Python linter is applied other than the one done locally by some maintainers and contributors.

Versions

master.

Additional Information

N/A.