Update nextcloud Docker tag to v30

[renovate[bot]]

This PR contains the following updates:

Package	Type	Update	Change
nextcloud		major	29.0.7 -> 30.0.0
nextcloud	final	major	29.0.7-fpm-alpine -> 30.0.0-fpm-alpine

---

Configuration

📅 Schedule: Branch creation - "before 4am on Monday" in timezone America/New_York, Automerge - At any time (no schedule defined).

🚦 Automerge: Disabled by config. Please merge this manually once you are satisfied.

♻ Rebasing: Whenever PR is behind base branch, or you tick the rebase/retry checkbox.

🔕 Ignore: Close this PR and you won't be reminded about these updates again.

---

• [ ] If you want to rebase/retry this PR, check this box

---

This PR was generated by Mend Renovate. View the repository job log.