Improve Pull Request template

[oshoma]

Your checklist for this pull request

Thank you for submitting a pull request! To speed up the review process, please follow this checklist:

• My Pull Request is small and focused on one topic so it can be reviewed easily
• My code follows the style guidelines of this project (make format)
• Commit messages are detailed
• I have performed a self-review of my code
• I commented hard-to-understand parts of my code
• I updated the documentation (docstrings, /docs)
• My changes generate no new warnings (or explain any new warnings and why they're ok)
• I have added tests that prove my fix is effective or that my feature works
• All tests pass when I run pytest tests (offline mode)

Additional steps for code with networking dependencies:

• I followed the offline and online testing guidelines
• All tests pass when I run pytest tests --external_api (online mode, making network calls)

Description

Clarify the checklists and instructions.

Add "Change Type".

💔Thank you!