test: fix integration harness lint findings

tests/integration/harness.py

@@ -12,6 +12,7 @@ and are excluded from ``repr`` and from every error message.
 from __future__ import annotations
 
 import atexit
+import contextlib
 import os
 import secrets
 import signal
@@ -136,10 +137,9 @@ def cleanup_resources(res: RunResources) -> None:
 def cleanup_all() -> None:
     """Clean every run still registered (atexit and signal path)."""
     for res in list(_ACTIVE.values()):
-        try:
+        # Best effort during interpreter exit: never let cleanup raise.
+        with contextlib.suppress(Exception):
             cleanup_resources(res)
-        except Exception:  # noqa: BLE001 - best effort during interpreter exit
-            pass
 
 
 def _signal_handler(signum: int, frame: FrameType | None) -> None: