node-red/.github/PULL_REQUEST_TEMPLATE.md

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## Types of changes

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- [ ] Bugfix (non-breaking change which fixes an issue)
- [ ] New feature (non-breaking change which adds functionality)

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## Proposed changes

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## Checklist
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- [ ] I have read the [contribution guidelines](https://github.com/node-red/node-red/blob/master/CONTRIBUTING.md)
- [ ] For non-bugfix PRs, I have discussed this change on the mailing list/slack team.
- [ ] I have run `grunt` to verify the unit tests pass
- [ ] I have added suitable unit tests to cover the new/changed functionality