ruff: Disable Pytest checks

We don't use pytest in our test machinery right now, and every new ruff
version starts to complain about more things. The recent tasks container
update started to fail our tests with

> PT027 Use `pytest.raises` instead of unittest-style `assertRaises`

Disable the PT rules again.

Fixes cockpit-project#1207

pyproject.toml

@@ -14,7 +14,6 @@ select = [
     "ISC",     # flake8-implicit-str-concat
     "PLE",     # pylint errors
     "PGH",     # pygrep-hooks
-    "PT",      # flake8-pytest-style
     "RSE",     # flake8-raise
     "RUF",     # ruff rules
     "T10",     # flake8-debugger
@@ -33,8 +32,6 @@ ignore = [
     "E731",  # Do not assign a `lambda` expression, use a `def`
     "FBT002", # Boolean default value in function definition
     "FBT003", # Boolean positional value in function call
-    "PT009", # Use a regular `assert` instead of unittest-style `assertEqual`
-    "PT011", # `pytest.raises(OSError)` is too broad
 ]
 # FIXME: we want 118, but needs fixing tests first
 line-length = 183