Update credentials.mdx

[SuryanshPandeyy]

Added code for Express in Validating credentials.

☕️ Reasoning

🧢 Checklist

• [ ] Documentation
• [ ] Tests
• [ ] Ready to be merged

🎫 Affected issues

📌 Resources

• Security guidelines
• Contributing guidelines
• Code of conduct
• Contributing to Open Source

[vercel[bot]]

The latest updates on your projects. Learn more about Vercel for Git ↗︎

Name	Status	Preview	Comments	Updated (UTC)
auth-docs	✅ Ready (Inspect)	Visit Preview	💬 Add feedback	Nov 23, 2024 4:58am

1 Skipped Deployment

| Name | Status | Preview | Comments | Updated (UTC) | | :--- | :----- | :------ | :------- | :------ | | **next-auth-docs** | ⬜️ Ignored ([Inspect](https://vercel.com/authjs/next-auth-docs/HcgZvWqSQoEEsHS16gAhzaD1meL4)) | [Visit Preview](https://next-auth-docs-git-fork-suryanshpandeyy-patch-2-authjs.vercel.app) | | Nov 23, 2024 4:58am |

[vercel[bot]]

@SuryanshPandeyy is attempting to deploy a commit to the authjs Team on Vercel.

A member of the Team first needs to authorize it.