Adds ruff, a drop-in replacement for black

[rachfop]

What was changed

Added isort: skip_file in the .gitignore file, because ruff will follow isorts commands. Replaced black with ruff in the .pyproject.toml` file.

• ran poe format && poe lint

There were a lot of changes made.

• removed unused imports
• removed/added white space according to pydoc style If this is too much, let me know and I close this PR and find a way later to make less changes. Looking for a quick win.

Why?

https://github.com/temporalio/sdk-python/issues/421

Checklist

1. Closes

2. How was this tested:

3. Any docs updates needed?

[cretz]

Can you work out the CI kinks? Make sure the app lints and tests all complete properly. Can mark as draft while you work through them.

[dandavison]

Thanks @rachfop! We followed through with this in https://github.com/temporalio/sdk-python/pull/566