docs: add a note to add openai credits

[tchia04]

📑 Description

Resolves the issue openapi API quota issue as discussed in the slack channel

Error: exhausted API quota for AI provider openai: error, status code: 429, message: You exceeded your current quota, please check your plan and billing details. For more information on this error, read the docs: https://platform.openai.com/docs/guides/error-codes/api-errors.

✅ Checks

• [X] My pull request adheres to the code style of this project
• [X] My code requires changes to the documentation
• [X] I have updated the documentation as required
• [X] All the tests have passed

ℹ Additional Information

@AlexsJones

The preview URL is not working. Here is the screenshot from my laptop

[netlify[bot]]

✅ Deploy Preview for meek-marigold-103c48 ready!

Name	Link
🔨 Latest commit	dcff7c1f0edeb3d33bf0e694ef4fb4a0ea4cb9bb
🔍 Latest deploy log	https://app.netlify.com/sites/meek-marigold-103c48/deploys/67d86f101715dd0008070f28
😎 Deploy Preview	https://deploy-preview-125--meek-marigold-103c48.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.

[AlexsJones]

Thanks for the contribution @tchia04 Can you please restructure it to be a bit simpler to read?

E.g.

If you see this error message: "...." 
Then do this...

Also it looks to be h1 size text, might be worth checking it's not too large.

Thanks!