chore(deps): Bump @nextcloud/dialogs in /build/frontend-legacy

Bumps [@nextcloud/dialogs](https://github.com/nextcloud-libraries/nextcloud-dialogs) from 7.2.0 to 7.3.0.
- [Release notes](https://github.com/nextcloud-libraries/nextcloud-dialogs/releases)
- [Changelog](https://github.com/nextcloud-libraries/nextcloud-dialogs/blob/main/CHANGELOG.md)
- [Commits](nextcloud-libraries/nextcloud-dialogs@v7.2.0...v7.3.0)

---
updated-dependencies:
- dependency-name: "@nextcloud/dialogs"
  dependency-version: 7.3.0
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]