Revise Copilot FAQ references in documentation

Updated the Copilot FAQ references for clarity.

Author: gewarren

docs/standard/serialization/system-text-json/customize-properties.md

@@ -273,7 +273,7 @@ change the serialized property name to use underscores between words.
 Use built-in serialization attributes.
 ```
 
-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