Fix okhttp-3.x and async-http-client-2.x did not overwrite the old trace header. (#5917)

* Fix okhttp-3.x and async-http-client-2.x did not overwrite the old trace header.

apm-sniffer/apm-sdk-plugin/asynchttpclient-2.x-plugin/src/main/java/org/apache/skywalking/apm/plugin/asynchttpclient/v2/ExecuteInterceptor.java

@@ -65,7 +65,7 @@ public class ExecuteInterceptor implements InstanceMethodsAroundInterceptor {
         CarrierItem next = contextCarrier.items();
         while (next.hasNext()) {
             next = next.next();
-            headers.add(next.getHeadKey(), next.getHeadValue());
+            headers.set(next.getHeadKey(), next.getHeadValue());
         }
     }
 

apm-sniffer/apm-sdk-plugin/okhttp-3.x-plugin/src/main/java/org/apache/skywalking/apm/plugin/okhttp/v3/AsyncCallInterceptor.java

@@ -78,7 +78,7 @@ public class AsyncCallInterceptor implements InstanceConstructorInterceptor, Ins
         CarrierItem next = contextCarrier.items();
         while (next.hasNext()) {
             next = next.next();
-            headerBuilder.add(next.getHeadKey(), next.getHeadValue());
+            headerBuilder.set(next.getHeadKey(), next.getHeadValue());
         }
         headersField.set(request, headerBuilder.build());
 

changes/changes-8.3.0.md

@@ -23,6 +23,7 @@ Release Notes.
 * Fix the default ignore mechanism isn't accurate enough bug.
 * Add the plugin for spring-kafka 1.3.x.
 * Add the plugin for Apache CXF 3.x.
+* Fix okhttp-3.x and async-http-client-2.x did not overwrite the old trace header.
 
 #### OAP-Backend
 * Add the `@SuperDataset` annotation for BrowserErrorLog.