test: format test suite (#2252)

tests/utils/__init__.py

@@ -1,3 +1,3 @@
 """
 Test utilities package.
-"""
+"""

tests/utils/import_isolation.py

@@ -26,6 +26,7 @@ from unittest.mock import MagicMock
 
 class MockLifecycleControlScope(enum.Enum):
     """Mock enum for breaking circular import in core.entities."""
+
     APPLICATION = 'application'
     PLATFORM = 'platform'
     PLUGIN = 'plugin'
@@ -190,4 +191,4 @@ def get_handler_modules_to_clear(handler_name: str) -> list[str]:
         'langbot.pkg.pipeline.process.handler',
         'langbot.pkg.pipeline.process.handlers',
         f'langbot.pkg.pipeline.process.handlers.{handler_name}',
-    ]
+    ]