Bump mermaid from 9.1.5 to 9.3.0 (#752)

CHangelog on https://github.com/mermaid-js/mermaid/releases

### Prerequisites

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- [ ] This pull request fixes a bug.
- [ ] This pull request adds a feature.
- [ ] This pull request introduces breaking change.

### Description

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### Issues Resolved

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### Checklist

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#### General

- [ ] Describe what changes are being made
- [ ] Explain why and how the changes were necessary and implemented
respectively
- [ ] Reference issue with `#<ISSUE_NO>` if applicable

#### Resources

- [ ] If you have changed any SCSS code, run `make release` to
regenerate all CSS files

#### Contributors

- [ ] Add yourself to `CONTRIBUTORS.md` if you aren't on it already

layouts/_default/baseof.html

@@ -25,7 +25,7 @@
   </main>
 
   {{ if .HasShortcode "mermaid" }}
-  <script src="https://cdn.jsdelivr.net/npm/mermaid@9.1.5/dist/mermaid.min.js" integrity="sha256-RqbL4xBKYq/iP+616ZrXdmaNyCuRX1mW7wjsHPfa8uY=" crossorigin="anonymous"></script>
+  <script src="https://cdn.jsdelivr.net/npm/mermaid@9.3.0/dist/mermaid.min.js" integrity="sha256-QdTG1YTLLTwD3b95jLqFxpQX9uYuJMNAtVZgwKX4oYU=" crossorigin="anonymous"></script>
   <script>
     mermaid.initialize({ startOnLoad: true });
   </script>