Bumps [korthout/backport-action](https://github.com/korthout/backport-action) from 1.3.1 to 1.4.0.
- [Release notes](https://github.com/korthout/backport-action/releases)
- [Commits](https://github.com/korthout/backport-action/compare/v1.3.1...v1.4.0

)

---
updated-dependencies:
- dependency-name: korthout/backport-action
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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