Update mermaid to version 8.9.2

What does this MR do?

Update mermaid to version 8.9.2 to fix a security issue. The issue is publicly available so I'm opening this on the canonical repository to get .com patched as soon as possible. I will make backports later for previous versions to be released in the next security release.

Screenshots (strongly suggested)

Does this MR meet the acceptance criteria?

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Security

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