Bump @nextcloud/auth from 0.3.1 to 1.2.0

Bumps [@nextcloud/auth](https://github.com/nextcloud/nextcloud-auth) from 0.3.1 to 1.2.0.
- [Release notes](https://github.com/nextcloud/nextcloud-auth/releases)
- [Changelog](https://github.com/nextcloud/nextcloud-auth/blob/master/CHANGELOG.md)
- [Commits](https://github.com/nextcloud/nextcloud-auth/compare/v0.3.1...v1.2.0

)

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