Ops 6609 update nextcloud version to 29

[RalfNellesCap]

Description

Links to Tickets or other pull requests

Screenshots of UI changes

Approval for review

• DEV: If the API or client code was changed, all necessary code generation or synchronization steps were completed and tested.
• QA: In addition to review, the code has been manually tested (if manual testing is possible)
• All points were discussed with the ticket creator, support-team or product owner. The code upholds all quality guidelines from the PR-template.

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