Deps: Bump pontos from 23.7.1 to 23.7.6 in /backport-pull-request

Bumps [pontos](https://github.com/greenbone/pontos) from 23.7.1 to 23.7.6.
- [Release notes](https://github.com/greenbone/pontos/releases)
- [Commits](greenbone/pontos@v23.7.1...v23.7.6)

---
updated-dependencies:
- dependency-name: pontos
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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