fix: simply from and to in message to string type

[ad1992]

📑 Summary

Change the type of from and to to string

Before

from?: { actor: string };
to?: { actor: string };

Now

from?:  string;
to?:string;

📏 Design Decisions

Describe the way your implementation works or what design decisions you made if applicable.

📋 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

[netlify]

✅ Deploy Preview for mermaid-js ready!

Name	Link
🔨 Latest commit	e102ac2
🔍 Latest deploy log	https://app.netlify.com/sites/mermaid-js/deploys/66327cc09506260008c952a2
😎 Deploy Preview	https://deploy-preview-5471--mermaid-js.netlify.app
📱 Preview on mobile	Toggle QR Code... Use your smartphone camera to open QR code link.

---

To edit notification comments on pull requests, go to your Netlify site configuration.

[codecov]

Codecov Report

Attention: Patch coverage is 0% with 13 lines in your changes are missing coverage. Please review.

Project coverage is 5.73%. Comparing base (8265e53) to head (e102ac2).

Additional details and impacted files

@@           Coverage Diff           @@
##           develop   #5471   +/-   ##
=======================================
  Coverage     5.73%   5.73%           
=======================================
  Files          277     277           
  Lines        42002   41999    -3     
  Branches       515     515           
=======================================
  Hits          2407    2407           
+ Misses       39595   39592    -3     

Flag	Coverage Δ
unit	5.73% <0.00%> (+<0.01%)	⬆️

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

Files	Coverage Δ
...ckages/mermaid/src/diagrams/sequence/sequenceDb.ts	0.00% <0.00%> (ø)
.../mermaid/src/diagrams/sequence/sequenceRenderer.ts	0.00% <0.00%> (ø)

[ad1992]

@sidharthv96 let me know if this looks good