Revert "More domains are required for Copilot. Taken from https://docs.github…"

This reverts commit 29763414d6.

platforms/dns-github-pilot.txt

@@ -1,7 +1,3 @@
 copilot-telemetry.githubusercontent.com
 copilot-proxy.githubusercontent.com
-githubcopilot.com
-github.com
-api.github.com
-default.exp-tas.com
-origin-tracker.githubusercontent.com
+githubcopilot.com