Introduce Ruff github CI with some basic linter rules

And also to help catching syntax errors on older Python versions.

src/bonsai/docs/guides/development/code_style.rst

@@ -2,7 +2,7 @@ Code style
 ============
 
 
-Black code formatter
+Code formatters
 -------------------------------
 For Python code formatting, we use `Black code formatter <https://pypi.org/project/black/>`__, 
 black settings are stored in the repository's pyproject.toml.
@@ -19,3 +19,17 @@ We have GitHub workflow `ci-black-formatting` to maintain black formatting acros
    # Format only some specific file.
    black src/bonsai/bonsai/bim/module/qto/operator.py
 
+
+There is also `ruff` with some basic linter rules (checked automatically by the same Github workflow).
+Which also helps maintaining consistency across the code base
+and ensure new Python syntax doesn't break code on older Python versions.
+
+``ruff`` can be installed using ``pip install ruff`` and files can be formatted with the following example commands:
+
+.. code-block:: bash
+   # Check issues for the entire repository.
+   ruff check
+   # Apply some automatic fixes, if available.
+   ruff check --fix
+   # Check only some specific file.
+   ruff src/bonsai/bonsai/bim/module/qto/operator.py