DOCS: update Mermaid Chart page

[huynhicode]

📑 Summary

This PR contains updates to the Mermaid Chart page.

Resolves # n/a

📏 Design Decisions

Design decisions made by the Mermaid Chart team.

📋 Tasks

Make sure you

• 📖 have read the contribution guidelines
• 💻 have added necessary unit/e2e tests.
• 📓 have added documentation. Make sure MERMAID_RELEASE_VERSION is used for all new features.
• 🔖 targeted develop branch

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 78.81%. Comparing base (c562ca0) to head (76801ff).
Report is 8 commits behind head on master.

Additional details and impacted files

@@             Coverage Diff             @@
##           master    #5495       +/-   ##
===========================================
+ Coverage    5.74%   78.81%   +73.06%     
===========================================
  Files         276      175      -101     
  Lines       41886    14531    -27355     
  Branches      514      868      +354     
===========================================
+ Hits         2407    11452     +9045     
+ Misses      39479     2871    -36608     
- Partials        0      208      +208     

Flag	Coverage Δ
e2e	84.28% <ø> (?)
unit	43.37% <ø> (+37.62%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

see 273 files with indirect coverage changes