winhttp/tests: Make sure proxy settings are restored.

[wine] / dlls / pstorec / pstorec.spec

@ stdcall -private DllCanUnloadNow()
@ stdcall -private DllGetClassObject(ptr ptr ptr)
@ stdcall -private DllRegisterServer()
@ stdcall -private DllUnregisterServer()
@ stub GetPStoreProvider
@ stdcall PStoreCreateInstance(ptr ptr ptr long)
@ stub PStoreEnumProviders