Add E4 rules to ruff

[johannaengland]

Codebase already fulfills these rules.

Tagging as discussion to invite discussion if/which of these rules we want.

Reference: https://docs.astral.sh/ruff/rules/#error-e

[lunkwill42]

Once we get into this class of linter violations: Won't they already be flagged by attempting to run black or ruff formatting of the codebase?

[johannaengland]

Once we get into this class of linter violations: Won't they already be flagged by attempting to run black or ruff formatting of the codebase?

I tested this by adding import os, sys and then running ruff format . and it was not changed.

[lunkwill42]

I tested this by adding import os, sys and then running ruff format . and it was not changed.

My bad. I tried to google what the E4 group of violations mean, and was left with the impression that they were all kinds of syntax errors: But now I'm thinking I must have found a reference from an entirely different tool, because it does not match up at all with the ruff docs we just looked.

Please disregard my earlier comment, I'm all for this.