build(deps): Bump @nextcloud/vue from 7.12.7 to 8.4.0

Bumps [@nextcloud/vue](https://github.com/nextcloud-libraries/nextcloud-vue) from 7.12.7 to 8.4.0.
- [Release notes](https://github.com/nextcloud-libraries/nextcloud-vue/releases)
- [Changelog](https://github.com/nextcloud-libraries/nextcloud-vue/blob/master/CHANGELOG.md)
- [Commits](nextcloud-libraries/nextcloud-vue@v7.12.7...v8.4.0)

---
updated-dependencies:
- dependency-name: "@nextcloud/vue"
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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