[ISSUE #9491] Remove the volatile declaration for the two variables requestsWrite and requestsRead in the GroupCommitService class (#9492)

Author: huanzhikang

store/src/main/java/org/apache/rocketmq/store/CommitLog.java

@@ -1610,8 +1610,8 @@ public CompletableFuture<PutMessageStatus> future() {
      * GroupCommit Service
      */
     class GroupCommitService extends FlushCommitLogService {
-        private volatile LinkedList<GroupCommitRequest> requestsWrite = new LinkedList<>();
-        private volatile LinkedList<GroupCommitRequest> requestsRead = new LinkedList<>();
+        private LinkedList<GroupCommitRequest> requestsWrite = new LinkedList<>();
+        private LinkedList<GroupCommitRequest> requestsRead = new LinkedList<>();
         private final PutMessageSpinLock lock = new PutMessageSpinLock();
 
         public void putRequest(final GroupCommitRequest request) {