chore(deps): Bump @nextcloud/vue from 8.19.0 to 8.21.0

Bumps [@nextcloud/vue](https://github.com/nextcloud-libraries/nextcloud-vue) from 8.19.0 to 8.21.0.
- [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@v8.19.0...v8.21.0)

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

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