update expert parallel init logic

[blacksheep-Aristotle]

Before submitting

• Lint code. If there are lint issues, please format the code first.

# Install and register `pre-commit` in the project folder
pip install pre-commit && pre-commit install

# Process previous code files separately
pre-commit run --file XXXX.py

• Add test cases into tests folder. If there are codecov issues, please add tests cases first.

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Description

调整PaddleNLP框架中moe parallel功能的实现方式，具体修改为：不再由PaddleNLP负责创建moe group，转而通过Paddle fleet的初始化流程来完成这一操作。

[paddle-bot]

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