Update dashboard-managed updates dev docs

[samin-cf]

Summary

Quick change to clarify that dashboard-managed updates do not require the user account to have admin privileges

Screenshots (optional)

Documentation checklist

• Is there a changelog entry (guidelines)? If you don't add one for something awesome and new (however small) — how will our customers find out? Changelogs are automatically posted to RSS feeds, the Discord, and X.
• The change adheres to the documentation style guide.
• If a larger change - such as adding a new page- an issue has been opened in relation to any incorrect or out of date information that this PR fixes.
• Files which have changed name or location have been allocated redirects.

[cloudflare-docs-bot]

AI Review

✅ Reviewed c7e2866 · 0 findings · incremental

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