chore: run ruff format over charm pin update code

[tonyandrewmeyer]

The only changes are from running tox -e fmt, and adding ruff format --preview check to the tox -e lint commands.

I don't think these changes are generally important, being in a separate file only used in CI, but ideally running tox -e fmt doesn't bring in unrelated changes when working on a branch, and we might as well be consistent.

[dimaqq]

A worthy change… was the file excluded from pre commit and/or tox?

if so, let’s include it.

if it was included , then I’m doubly sorry for having merged it regardless!

[tonyandrewmeyer]

A worthy change… was the file excluded from pre commit and/or tox?

if so, let’s include it.

It was included in the formatting but not in the linting. I've added that too, now.