Remove unused import from settings regression tests

Address CodeQL py/unused-import follow-up in PR #1478. Refs #1477.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Author: nadoylemsft

functional_tests/test_app_settings_store_consistency.py

@@ -16,7 +16,6 @@
 from pathlib import Path
 import socket
 import secrets
-import sys
 from types import SimpleNamespace
 
 import pytest