refactor: remove unnecessary check.

source/libs/executor/src/executorimpl.c

@@ -1885,10 +1885,8 @@ void extractQualifiedTupleByFilterResult(SSDataBlock* pBlock, const int8_t* rowR
       }
 
       // write back
-      if (pBlock->info.rows > 0) {
       colDataAssign(pSrc, pDst, pBlock->info.rows);
     }
-    }
     blockDataDestroy(px);  // fix memory leak
   } else {
     // do nothing