Bump mermaid and @docusaurus/theme-mermaid#3

dependabot[bot] wants to merge 1 commit intomasterpostgres-ai/docs:masterfrom

dependabot/npm_and_yarn/multi-3d96c9257bpostgres-ai/docs:dependabot/npm_and_yarn/multi-3d96c9257bCopy head branch name to clipboard