docs: fix broken links

[halvaradop]

☕️ Reasoning

This pull request updates broken links to correctly reference the Credentials Provider.
The PR addresses issue #13195.

🧢 Checklist

• Documentation
• Tests
• Ready to be merged

🎫 Affected issues

#13195

📌 Resources

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

[vercel]

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Project	Deployment	Preview	Comments	Updated (UTC)
auth-docs	Ready	Preview	Comment	Aug 27, 2025 11:53pm

1 Skipped Deployment

Project	Deployment	Preview	Comments	Updated (UTC)
next-auth-docs	Ignored	Preview		Aug 27, 2025 11:53pm

[vercel]

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[codecov]

Codecov Report

❌ Patch coverage is 0% with 2 lines in your changes missing coverage. Please review.
✅ Project coverage is 38.02%. Comparing base (39dd3b9) to head (bd868d9).

Files with missing lines	Patch %	Lines
packages/core/src/providers/index.ts	0.00%	2 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #13197      +/-   ##
==========================================
- Coverage   38.76%   38.02%   -0.75%     
==========================================
  Files         200      199       -1     
  Lines       32323    31924     -399     
  Branches     1393     1340      -53     
==========================================
- Hits        12529    12138     -391     
+ Misses      19794    19786       -8     

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