Use Ruff as formatter in Jupyter Lab

[redeboer]

Since #301, black and isort are still installed in environments with Jupyter Lab, because jupyterlab-code-formatter does not yet support formatting with Ruff. There seems to be no good solution yet. Some relevant links:

• https://github.com/python-lsp/python-lsp-ruff seems not to have a formatting operation in Jupyter Lab
• https://gist.github.com/jbwhit/eecdd1cac2756df85ad165f437445b0b
• https://github.com/ryantam626/jupyterlab_code_formatter/issues?q=ruff

[redeboer]

This works since jupyterlab-code-formatter v3.0.0 🎉