tests: Adjust whitespace to satisfy ruff

I don't quite get this one. voluptuous belongs with the third party imports,
but it is out of alphabetical order. Or does import always come before
from ... import?

tests/test_device_config.py

@@ -1,8 +1,8 @@
 """Test the config parser"""
 from unittest import IsolatedAsyncioTestCase
 from unittest.mock import MagicMock
-import voluptuous as vol
 
+import voluptuous as vol
 from fuzzywuzzy import fuzz
 from homeassistant.components.sensor import SensorDeviceClass