Include additional tags in AggregateEntry test equality contract

The helper's equals() omitted getAdditionalTags() while keyHash folds it in, so
entries differing only in additional tags compared equal yet produced different
hash codes -- letting matcher-based tests silently accept missing or wrong
additional dimensions. Compare the arrays positionally (schema order) to match
the key identity.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

Author: dougqh

dd-trace-core/src/test/java/datadog/trace/common/metrics/AggregateEntryTestUtils.java

@@ -1,6 +1,7 @@
 package datadog.trace.common.metrics;
 
 import datadog.trace.bootstrap.instrumentation.api.UTF8BytesString;
+import java.util.Arrays;
 import java.util.Collections;
 import java.util.List;
 import java.util.Objects;
@@ -174,7 +175,10 @@ public static boolean equals(AggregateEntry a, AggregateEntry b) {
         && a.getPeerTags().equals(b.getPeerTags())
         && Objects.equals(a.getHttpMethod(), b.getHttpMethod())
         && Objects.equals(a.getHttpEndpoint(), b.getHttpEndpoint())
-        && Objects.equals(a.getGrpcStatusCode(), b.getGrpcStatusCode());
+        && Objects.equals(a.getGrpcStatusCode(), b.getGrpcStatusCode())
+        // Additional tags are part of the key (folded into keyHash in schema order), so entries
+        // that differ only in additional tags must not compare equal.
+        && Arrays.equals(a.getAdditionalTags(), b.getAdditionalTags());
   }
 
   /**