Fix database property name in the Connecting.md doc

[sfc-gh-ymelnyk]

Description

The property should be db, but examples in the docs misleadingly state database.

Checklist

• Code compiles correctly
• Code is formatted according to Coding Conventions
• Created tests which fail without the change (if possible)
• All tests passing (dotnet test)
• Extended the README / documentation, if necessary
• Provide JIRA issue id (if possible) or GitHub issue id in PR name

[github-actions]

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[sfc-gh-ymelnyk]

I have read the CLA Document and I hereby sign the CLA