update MariaDB documentation links from kb/ to docs/ (#20968)

[ti-chi-bot]

This is an automated cherry-pick of #20968

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close #20964

The MariaDB Knowledge Base has been migrated to a new documentation platform (mariadb.com/docs/). Many links using the old kb/ path structure are now broken (returning 404 errors) or being redirected, which impacts user experience and documentation reliability.

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@Oreoxmt This PR has conflicts, I have hold it.
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[Oreoxmt]

/unhold

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/approve

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