Maintenance: update docs to use self-hosted mermaid.js script

[dreamorosi]

Summary

We use mermaid for diagrams in a few of our documentation pages and the documentation engine we use defaults to loading the script from a remote CDN.

Why is this needed?

To further improve our security posture we should switch to self hosting the script.

Which area does this relate to?

Other

Solution

Update the mkdocs.yml file and point it to https://docs.powertools.aws.dev/shared/mermaid.min.js

Acknowledgment

• This request meets Powertools for AWS Lambda (Java) Tenets
• Should this be considered in other Powertools for AWS Lambda (Java) languages? i.e. Python, TypeScript