Core SDK 1.7.1

Updates

1. Fix

   Fixed: `ActionScheduler` doesn't generate GC allocation (used to be 40 bytes) each frame anymore.

2. Fix

   Fixed: Added a link.xml generator to make sure all required service assemblies are properly preserved in build with code stripping enabled. Only services providing a `IServiceComponent` are listed in this link file.

3. Fix

   Fixed: Failed telemetry request no longer log errors when they fail, unless `ENABLE_UNITY_SERVICES_CORE_TELEMETRY_LOGGING` is enabled as scripting define.

4. Fix

   Fixed: All `ActionScheduler` registered during play mode are now properly unregistered when exiting playmode.