docs: fix API key docs url

[zmezei]

Proposed Changes

[describe the changes here...]

Linked Issues

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Types of changes

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• Bug fix (non-breaking change that fixes an issue).
• New feature added (non-breaking change that adds functionality).
• Breaking change (fix or feature that would cause existing functionality to stop working as expected).
• Documentation update.
• Something else (e.g., tests, scripts, example, deployment, infrastructure).

Checklist

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• I have read the CONTRIBUTING guide
• Checks and tests pass locally

If applicable

• I have added tests that prove my fix is effective or that my feature works
• I have checked that code coverage does not decrease
• I have added/updated the documentation

Further comments

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