Switch linting to Ruff

[SeanBryan51]

This change fixes minor linter warnings from the Ruff linter and adds a basic ruff.toml configuration.

Fixes #145

[codecov[bot]]

Codecov Report

Merging #164 (56448d4) into main (b683d29) will increase coverage by 0.21%. Report is 12 commits behind head on main. The diff coverage is 99.52%.

@@            Coverage Diff             @@
##             main     #164      +/-   ##
==========================================
+ Coverage   88.75%   88.97%   +0.21%     
==========================================
  Files          27       26       -1     
  Lines        1628     1660      +32     
==========================================
+ Hits         1445     1477      +32     
  Misses        183      183              

Files	Coverage Δ
benchcab/cli.py	100.00% <100.00%> (ø)
benchcab/comparison.py	61.36% <100.00%> (ø)
benchcab/config.py	100.00% <100.00%> (ø)
benchcab/environment_modules.py	85.00% <100.00%> (+0.38%)	:arrow_up:
benchcab/fluxsite.py	83.04% <100.00%> (+0.09%)	:arrow_up:
benchcab/internal.py	90.47% <ø> (ø)
benchcab/repository.py	99.00% <100.00%> (+0.01%)	:arrow_up:
benchcab/utils/fs.py	100.00% <100.00%> (ø)
benchcab/utils/pbs.py	100.00% <ø> (ø)
benchcab/utils/subprocess.py	100.00% <100.00%> (ø)
... and 14 more