Fix HTML links in examples index

[bmerkle]

This pull request makes minor corrections to the example links in the docs/examples/index.md file. The main change is fixing the HTML anchor tags to ensure the href attributes are properly quoted, which improves link reliability and HTML validity.

• Documentation fixes:
  • Fixed missing opening quotes in the href attributes for the spinner and stacks example links in docs/examples/index.md. [1] [2]fixed 2 invalid html links

📝 Summary

🔍 Description of Changes

📋 Checklist

• I have read the contributor guidelines.
• For large changes, or changes that affect the public API: this change was discussed or approved through an issue, on Discord, or the community discussions (Please provide a link if applicable).
• I have added tests for the changes made.
• I have run the code and verified that it works as expected.

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Project	Deployment	Preview	Comments	Updated (UTC)
marimo-docs	Ready	Preview	Comment	Nov 2, 2025 10:20pm

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[bmerkle]

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