build(deps-dev): bump @nextcloud/eslint-config from 6.1.0 to 8.4.2

Bumps [@nextcloud/eslint-config](https://github.com/nextcloud-libraries/eslint-config) from 6.1.0 to 8.4.2.
- [Release notes](https://github.com/nextcloud-libraries/eslint-config/releases)
- [Changelog](https://github.com/nextcloud-libraries/eslint-config/blob/main/CHANGELOG.md)
- [Commits](nextcloud-libraries/eslint-config@v6.1.0...v8.4.2)

---
updated-dependencies:
- dependency-name: "@nextcloud/eslint-config"
  dependency-version: 8.4.2
  dependency-type: direct:development
  update-type: version-update:semver-major
...

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Author: dependabot[bot]