enh: adjust logging level of sync-heartbeat to TRACE

source/libs/sync/src/syncUtil.c

@@ -364,7 +364,7 @@ void syncLogRecvHeartbeat(SSyncNode* pSyncNode, const SyncHeartbeat* pMsg, int64
   if (timeDiff > SYNC_HEARTBEAT_SLOW_MS) {
     pSyncNode->hbSlowNum++;
 
-    sNInfo(pSyncNode,
+    sNTrace(pSyncNode,
             "recv sync-heartbeat from dnode:%d slow {term:%" PRId64 ", commit-index:%" PRId64 ", min-match:%" PRId64
             ", ts:%" PRId64 "}, %s, net elapsed:%" PRId64,
             DID(&pMsg->srcId), pMsg->term, pMsg->commitIndex, pMsg->minMatchIndex, pMsg->timeStamp, s, timeDiff);