COMP: Fix ruff settings to avoid enforcing pytest style

Since the base class associated with scripted module class `ScriptedLoadableModuleTest`
is `unittest.TestCase`, using function like assertEqual is legitimate and
should not be replaced with `assert`.

References:
* https://docs.python.org/3/library/unittest.html#unittest.TestCase
* https://docs.astral.sh/ruff/rules/#flake8-pytest-style-pt

pyproject.toml

@@ -18,7 +18,6 @@ select = [
     "PGH",         # pygrep-hooks
     "PIE",         # flake8-pie
     "PL",          # pylint
-    "PT",          # flake8-pytest-style
     "RET",         # flake8-return
     "RUF",         # Ruff-specific
     "S",           # flake8-bandit