cherrypick/.github/pull_request_template.md

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## What
<!-- このPRで何をしたのか？ どう変わるのか？ -->
<!-- What did you do with this PR? How will it change things? -->

## Why
<!-- なぜそうするのか？ どういう意図なのか？ 何が困っているのか？ -->
<!-- Why do you do it? What are your intentions? What is the problem? -->

## Additional info (optional)
<!-- テスト観点など -->
<!-- Test perspective, etc -->

## Checklist
- [ ] Read the [contribution guide](https://github.com/kokonect-link/cherrypick/blob/develop/CONTRIBUTING.md)
- [ ] Test working in a local environment
- [ ] (If needed) Add story of storybook
- [ ] (If needed) Update CHANGELOG.md
- [ ] (If possible) Add tests