docs: Update app maintainers

[ChristophWurst]

To align with https://github.com/nextcloud/groupware/pull/86.

[codecov[bot]]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Project coverage is 23.47%. Comparing base (9d1688c) to head (73b1758). Report is 47 commits behind head on main.

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #6467 +/- ## ========================================= Coverage 23.47% 23.47% - Complexity 453 454 +1 ========================================= Files 247 247 Lines 11712 11708 -4 Branches 2222 2212 -10 ========================================= Hits 2749 2749 + Misses 8643 8639 -4 Partials 320 320 ``` | [Flag](https://app.codecov.io/gh/nextcloud/calendar/pull/6467/flags?src=pr&el=flags&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=nextcloud) | Coverage Δ | | |---|---|---| | [javascript](https://app.codecov.io/gh/nextcloud/calendar/pull/6467/flags?src=pr&el=flag&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=nextcloud) | `15.05% <ø> (ø)` | | | [php](https://app.codecov.io/gh/nextcloud/calendar/pull/6467/flags?src=pr&el=flag&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=nextcloud) | `59.42% <ø> (+0.10%)` | :arrow_up: | Flags with carried forward coverage won't be shown. [Click here](https://docs.codecov.io/docs/carryforward-flags?utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=nextcloud#carryforward-flags-in-the-pull-request-comment) to find out more.

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---

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[ChristophWurst]

/backport to stable5.0

[backportbot[bot]]

The backport to stable5.0 failed. Please do this backport manually.

# Switch to the target branch and update it
git checkout stable5.0
git pull origin stable5.0

# Create the new backport branch
git checkout -b backport/6467/stable5.0

# Cherry pick the change from the commit sha1 of the change against the default branch
# This might cause conflicts, resolve them
git cherry-pick 73b1758b

# Push the cherry pick commit to the remote repository and open a pull request
git push origin backport/6467/stable5.0

Error: No changes found in backport branch

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Learn more about backports at https://docs.nextcloud.com/server/stable/go.php?to=developer-backports.