Bump mermaid from 8.9.0 to 8.13.8

Bumps [mermaid](https://github.com/knsv/mermaid) from 8.9.0 to 8.13.8.
- [Release notes](https://github.com/knsv/mermaid/releases)
- [Changelog](https://github.com/mermaid-js/mermaid/blob/develop/docs/CHANGELOG.md)
- [Commits](https://github.com/knsv/mermaid/compare/8.9.0...8.13.8)

---
updated-dependencies:
- dependency-name: mermaid
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <support@github.com>

package.json

@@ -5,7 +5,7 @@
     "github-markdown-css": "^4.0.0",
     "jquery": "^3.5.0",
     "mathjax": "^3.1.2",
-    "mermaid": "^8.9.0",
+    "mermaid": "^8.13.8",
     "rollup": "^2.38.5"
   }
 }