chore(.): Ignore flake8 S101

Previous attempts to selectively disable this warning per-file failed,
as flake8 does not correctly normalise paths for `per-file-ignores`.
Until resolved, we disable this check as `assert` statements are
extremely unlikely out of tests files.

See PyCQA/flake8#693

pyproject.toml

@@ -37,9 +37,8 @@ float_to_top = false
 
 [tool.flake8]
 select = "ANN,B,B9,C,C4,D,DAR,F,S,SC"
-ignore = "ANN101"
+ignore = "ANN101,S101"
 exclude = "docs/conf.py"
-per-file-ignore = "tests/*:S101"
 max-line-length = 88
 max-complexity = 10
 docstring-convention = "numpy"