Add SQL Server codespaces code examples

[cmaneu]

Why:

Closes #21581

What's being changed (if available, include any code snippets, screenshots, or gifs):

Add a new SQL sample in the Code examples section of Codespaces docs landing page

Check off the following:

• [x] I have reviewed my changes in staging (look for the "Automatically generated comment" and click the links in the "Preview" column to view your latest changes).
• [x] For content changes, I have completed the self-review checklist.

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[cmaneu]

I don't have the staging address, however I've reviewed https://docs-21580-ec9634.preview.ghdocs.com/en

[cmwilson21]

@cmaneu Thank you for opening a PR and linking it to your issue! ✨

I'll get this triaged for review ⚡

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