fix: orm GetTaskOfProver

Author: yiweichi

coordinator/internal/orm/prover_task.go

@@ -156,9 +156,10 @@ func (o *ProverTask) GetTaskOfProver(ctx context.Context, taskType message.Proof
 	db = db.Where("task_id", taskID)
 	db = db.Where("prover_public_key", proverPublicKey)
 	db = db.Where("prover_version", proverVersion)
+	db = db.Limit(1)
 
 	var proverTask ProverTask
-	err := db.First(&proverTask).Error
+	err := db.Find(&proverTask).Error
 	if err != nil {
 		return nil, fmt.Errorf("ProverTask.GetTaskOfProver error: %w, taskID: %v, publicKey:%s", err, taskID, proverPublicKey)
 	}