Bump christophwurst/nextcloud from 20.0.1 to 20.0.4

Bumps [christophwurst/nextcloud](https://github.com/ChristophWurst/nextcloud_composer) from 20.0.1 to 20.0.4.
- [Release notes](https://github.com/ChristophWurst/nextcloud_composer/releases)
- [Commits](https://github.com/ChristophWurst/nextcloud_composer/compare/v20.0.1...v20.0.4

)

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