Enable some more ruff lints

[WhyNotHugo]

Nothing serious found here, mostly minor lints.

[codecov]

Codecov Report

Merging #369 (22bdfa3) into main (a343a59) will decrease coverage by 0.25%.
Report is 3 commits behind head on main.
The diff coverage is 72.06%.

@@            Coverage Diff             @@
##             main     #369      +/-   ##
==========================================
- Coverage   78.99%   78.74%   -0.25%     
==========================================
  Files          29       29              
  Lines        1947     1943       -4     
  Branches      241      240       -1     
==========================================
- Hits         1538     1530       -8     
- Misses        293      299       +6     
+ Partials      116      114       -2     

Files Changed	Coverage Δ
payments/core.py	83.33% <ø> (ø)
payments/urls.py	0.00% <0.00%> (ø)
payments/models.py	75.78% <20.00%> (-0.60%)	⬇️
payments/mercadopago/__init__.py	86.31% <33.33%> (-0.92%)	⬇️
payments/__init__.py	82.00% <50.00%> (ø)
payments/cybersource/__init__.py	65.95% <51.51%> (-0.62%)	⬇️
payments/authorizenet/forms.py	66.66% <63.15%> (+2.66%)	⬆️
payments/braintree/forms.py	88.88% <66.66%> (-3.42%)	⬇️
payments/stripe/__init__.py	67.30% <66.66%> (ø)
payments/stripe/providers.py	72.99% <66.66%> (ø)
... and 16 more

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