Motivation

1. 新增模型训练代码提交规范

Modification

1. 添加CONTRIBUTING.md文档，其内容为模型训练代码提交规范
2. 在README.md文档中，添加对上述文档的链接指引

Self-test (Optional)

不涉及

BC-breaking (Optional)

不涉及

Checklist

Before PR:

• The new code needs to comply with the Clean Code specification.
• The PR content is self-checked, and the expression can be clear and the writing standardized

After PR:

• CLA has been signed and all committers have signed the CLA in this PR.
• The ci-pipeline is passed, Code Check is passed.