PULL_REQUEST_TEMPLATE.md

Description

Checklist

• An issue was first created before opening this pull request
• The new code follows the contribution guidelines
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• I have added tests to ensure that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes