other: add logs.

source/dnode/snode/src/snode.c

@@ -67,6 +67,7 @@ int32_t sndExpandTask(SSnode *pSnode, SStreamTask *pTask, int64_t ver) {
 
   pTask->pState = streamStateOpen(pSnode->path, pTask, false, -1, -1);
   if (pTask->pState == NULL) {
+    qError("s-task:%s failed to open state for task", pTask->id.idStr);
     return -1;
   }
 

source/dnode/vnode/src/tq/tq.c

@@ -969,6 +969,7 @@ int32_t tqExpandTask(STQ* pTq, SStreamTask* pTask, int64_t ver) {
 
     pTask->pState = streamStateOpen(pTq->pStreamMeta->path, pSateTask, false, -1, -1);
     if (pTask->pState == NULL) {
+      tqError("s-task:%s (vgId:%d) failed to open state for task", pTask->id.idStr, vgId);
       return -1;
     }