Bump mermaid from 10.9.0 to 10.9.3 in /openbullet2-web-client

Bumps [mermaid](https://github.com/mermaid-js/mermaid) from 10.9.0 to 10.9.3.
- [Release notes](https://github.com/mermaid-js/mermaid/releases)
- [Changelog](https://github.com/mermaid-js/mermaid/blob/develop/CHANGELOG.md)
- [Commits](mermaid-js/mermaid@v10.9.0...v10.9.3)

---
updated-dependencies:
- dependency-name: mermaid
  dependency-type: indirect
...

Signed-off-by: dependabot[bot] <[email protected]>