build(deps-dev): Bump @nextcloud/upload

Bumps [@nextcloud/upload](https://github.com/skjnldsv/nextcloud-upload) from 1.0.0-beta.14 to 1.0.0-beta.15.
- [Release notes](https://github.com/skjnldsv/nextcloud-upload/releases)
- [Commits](nextcloud-libraries/nextcloud-upload@v1.0.0-beta.14...v1.0.0-beta.15)

---
updated-dependencies:
- dependency-name: "@nextcloud/upload"
  dependency-type: direct:development
  update-type: version-update:semver-patch
...

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