fix: resolve flake8 E402/F401 in test file

- Remove unused MagicMock import (F401)
- Move sys.path.insert above third-party imports and add noqa: E402
  to the two imports that must follow it (E402)

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

tests/test_hwmon.py

@@ -1,11 +1,13 @@
 """Tests for SystemHealthMonitor pure methods — no external processes or filesystem."""
 import sys
 import os
-from unittest.mock import patch, MagicMock
-sys.path.insert(0, os.path.dirname(os.path.dirname(__file__)))
 
 import pytest
-from hwmonDaemon import SystemHealthMonitor
+
+sys.path.insert(0, os.path.dirname(os.path.dirname(__file__)))
+
+from unittest.mock import patch  # noqa: E402
+from hwmonDaemon import SystemHealthMonitor  # noqa: E402
 
 
 @pytest.fixture(scope='module')