Bump cdav-library from `8a8d42f` to `75c1b97`

Bumps [cdav-library](https://github.com/nextcloud/cdav-library) from `8a8d42f` to `75c1b97`.
- [Release notes](https://github.com/nextcloud/cdav-library/releases)
- [Commits](https://github.com/nextcloud/cdav-library/compare/8a8d42fad2a9bc9567b353c49559438347d110ee...75c1b972bffa4f665ff26fd4e4f85856608ad434

)

---
updated-dependencies:
- dependency-name: cdav-library
  dependency-type: direct:production
...

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