Update to Mermaid v9.0.0

For: gitlab#359321 (closed), updates the version of Mermaid available to Mermaid diagrams published to GitLab Docs site.

• Before: https://docs.gitlab.com/ee/development/architecture.html#component-diagram
• After: http://eread-update-to-mermaid-v9-0-0.35.193.151.162.nip.io/ee/development/architecture.html#component-diagram

CC @aqualls