Revise Copilot usage information in deserialization.md

Updated the text regarding GitHub Copilot to emphasize reviewing suggestions and provided a link to GitHub's FAQs.

Author: gewarren

docs/standard/serialization/system-text-json/deserialization.md

@@ -99,7 +99,7 @@ Map property names & values.
 Provide example output.
 ```
 
-GitHub Copilot is powered by AI, so surprises and mistakes are possible. For more information, see [Copilot FAQs](https://aka.ms/copilot-general-use-faqs).
+Review Copilot's suggestions before applying them. For more information GitHub Copilot, see GitHub's [FAQs](https://github.com/features/copilot#faq).
 
 ## See also