fix:fix ChatZhipuAI tool call bug (#26693)
- [ ] **PR title**: "community:fix ChatZhipuAI tool call bug"
- [ ] **Description:** ZhipuAI api response as follows:
{'id': '20240920132549e379a9152a6a4d7c', 'created': 1726809949, 'model':
'glm-4-flash', 'choices': [{'index': 0, 'finish_reason': 'tool_calls',
'delta': {'role': 'assistant', 'tool_calls': [{'id':
'call_20240920132549e379a9152a6a4d7c', 'index': 0, 'type': 'function',
'function': {'name': 'get_datetime_offline', 'arguments': '{}'}}]}}]}
so, tool_calls = dct.get("tool_call", None) in
_convert_delta_to_message_chunk should be "tool_calls"
