test: 测试套件自隔离与全量离线化（collection 清零 + 杜绝真实网络） (#5873)

tests/test_transfer_history_retransfer.py

@@ -1,10 +1,5 @@
-from types import ModuleType, SimpleNamespace
-import sys
+from types import SimpleNamespace
 
-# The endpoint import pulls in a wide plugin/helper graph. Some optional modules are
-# not present in this test environment, so stub them before importing the endpoint.
-sys.modules.setdefault("app.helper.sites", ModuleType("app.helper.sites"))
-setattr(sys.modules["app.helper.sites"], "SitesHelper", object)
 
 from app.api.endpoints.transfer import (
     manual_transfer,