[rule] simpify x if x else y to x or y

[dorschw]

I wanted to suggest it to flake8-simplify but there hasn't been much activity there in a while, and flake8-pie says they're deprecated and link to ruff.

x = ...
- y = x if x else 'default'
+ y = x or 'default'

It could be a bit confusing to newcomers, but cleaner, imo, to anyone familiar with ternaries in Python.

[evanrittenhouse]

I think the logic here should be pretty closely related to ExprOrTrue.

[evanrittenhouse]

@charliermarsh I can implement this if we want to do it, but it'll diverge from upstream. Is that alright?

[dosisod]

This is implemented as FURB110 in Refurb (see #1348), so you could put this check under that category.

[charliermarsh]

Closed by #10687.