[Feature][community] Add pull requests template for repo website

[zhongjiajie]

Search before asking

• I had searched in the issues and found no similar feature requirement.

Description

Add PR template to repo website:

• Using English version for pictures instead of both English and Chinese version
• Change dev directory document if it needs (new feature, bug fix, TOC chage)

Use case

No response

Related issues

No response

Are you willing to submit a PR?

• Yes I am willing to submit a PR!

Code of Conduct

• I agree to follow this project's Code of Conduct

[github-actions]

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