feat: add MergeRecordUtil comment

Author: lucas-myx

arex-instrumentation-api/src/main/java/io/arex/inst/runtime/util/MergeRecordUtil.java

@@ -14,7 +14,9 @@
 import java.util.concurrent.LinkedBlockingQueue;
 
 /**
- * merge record
+ * To solve the problem of insufficient consume capacity of downstream DataServices.
+ * by controlling the speed at which producers produce mockers.
+ * multiple producer -> single consumer
  */
 public class MergeRecordUtil {
     private static final AgentSizeOf agentSizeOf = AgentSizeOf.newInstance();