Disable byte-buddy's Nexus mechanism (we don't need it, and it triggers use of Unsafe) (#9569)

Author: mcculls

dd-java-agent/agent-builder/src/main/java/datadog/trace/agent/tooling/AgentInstaller.java

@@ -55,6 +55,7 @@ public class AgentInstaller {
 
   static {
     addByteBuddyRawSetting();
+    disableByteBuddyNexus();
     // register weak map supplier as early as possible
     WeakMaps.registerAsSupplier();
     circularityErrorWorkaround();
@@ -335,6 +336,11 @@ private static void addByteBuddyRawSetting() {
     }
   }
 
+  private static void disableByteBuddyNexus() {
+    // disable byte-buddy's Nexus mechanism (we don't need it, and it triggers use of Unsafe)
+    SystemProperties.set("net.bytebuddy.nexus.disabled", "true");
+  }
+
   private static AgentBuilder.RedefinitionStrategy.Listener redefinitionStrategyListener(
       final Set<InstrumenterModule.TargetSystem> enabledSystems) {
     if (enabledSystems.contains(InstrumenterModule.TargetSystem.IAST)) {