saleor-dashboard/.github/PULL_REQUEST_TEMPLATE.md

I want to merge this change because...

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Pull Request Checklist

1. All visible strings are translated with proper context.
2. All data-formatting is locale-aware (dates, numbers, and so on).
3. Number of API calls is optimized.
4. The changes are tested.
5. Type definitions are up to date.
6. Changes are mentioned in the changelog.