lint & format graph/tests/*.py

[jGaboardi]

xref #589

This PR formats and lints libpysal/graph/tests/*.py

[codecov]

Codecov Report

Merging #619 (59c8d7a) into main (b027196) will decrease coverage by 0.0%.
The diff coverage is 100.0%.

@@           Coverage Diff           @@
##            main    #619     +/-   ##
=======================================
- Coverage   84.4%   84.4%   -0.0%     
=======================================
  Files        139     139             
  Lines      14881   14862     -19     
=======================================
- Hits       12559   12540     -19     
  Misses      2322    2322             

Files	Coverage Δ
libpysal/graph/_utils.py	89.3% <100.0%> (ø)
libpysal/graph/tests/test_base.py	100.0% <100.0%> (ø)
libpysal/graph/tests/test_builders.py	100.0% <100.0%> (ø)
libpysal/graph/tests/test_contiguity.py	100.0% <100.0%> (ø)
libpysal/graph/tests/test_kernel.py	100.0% <100.0%> (ø)
libpysal/graph/tests/test_plotting.py	100.0% <ø> (ø)
libpysal/graph/tests/test_set_ops.py	100.0% <100.0%> (ø)
libpysal/graph/tests/test_spatial_lag.py	100.0% <100.0%> (ø)
libpysal/graph/tests/test_triangulation.py	84.2% <100.0%> (-0.1%)	⬇️
libpysal/graph/tests/test_utils.py	98.8% <100.0%> (ø)

[jGaboardi]

@martinfleis This one's a bit bigger diff than ideal, but the vast majority are upper->lowercase variable renaming in tests.

[martinfleis]

Just one note. Thanks!