feat: improve pull request template

- remove checklist which almost nobody uses
- make the text motivating instead of requiring

.github/PULL_REQUEST_TEMPLATE.md

@@ -1,29 +1,14 @@
-## Proposed changes
-
 <!--
-Describe the big picture of your changes here to communicate to the maintainers
-why we should accept this pull request. If it fixes a bug or resolves a feature
-request, be sure to link to that issue.
--->
+♥ Thank you for submitting a pull request. ♥
 
-## Checklist
+We will review it in a timely manner, but please follow the CI checks to see
+any problems it might discover.
 
-<!--
-Put an `x` in the boxes that apply. You can also fill these out after creating
-the PR. If you're unsure about any of them, don't hesitate to ask. We're here to
-help! This is simply a reminder of what we are going to look for before merging
-your code.
--->
+Want to make a perfect pull request?
 
-- [ ] Lint and unit tests pass locally with my changes.
-- [ ] I have added tests that prove my fix is effective or that my feature works.
-- [ ] I have added documentation to describe my feature.
-- [ ] I have squashed my commits into logic units.
-- [ ] I have described the changes in the commit messages.
-
-## Other information
-
-<!--
-Any other information that is important to this PR such as screenshots of how
-the component looks before and after the change.
+• Keep the pull request reasonably sized. Creating more pull request is sometimes better.
+• Describe what the pull request does and what issues it does address.
+• Ensure that lint and unit tests pass.
+• Add tests that prove that the fix is effective or that the new feature works.
+• Describe any new features or changed behavior in the documentation.
 -->