see. https://github.com/FreeOpcUa/opcua-asyncio/pull/878#issuecomment-1120423672

- help for type check
- highlight function arguments types

Closes #885

use unittest AsyncMock instead of CoroutineMock which creates warnings

DeprecationWarning: The explicit passing of coroutine objects to asyncio.wait() is deprecated since Python 3.8, and scheduled for removal in Python 3.11.

and tests

- Fix default value for structs with lists
- Rename server-custom-structures-amd-enums.py
- Fix Enum in server-custom-structures-amd-enums.py

- DataSetFieldFlags is only from type UInt16 instead of UInt32
- Default Optionset to UInt32 instead of Int32