Fix wrong error check (#12310)

store/sqlstore/audit_store.go

@@ -87,7 +87,7 @@ func (s SqlAuditStore) PermanentDeleteBatch(endTime int64, limit int64) (int64,
 
 	rowsAffected, err1 := sqlResult.RowsAffected()
 	if err1 != nil {
-		return 0, model.NewAppError("SqlAuditStore.PermanentDeleteBatch", "store.sql_audit.permanent_delete_batch.app_error", nil, ""+err.Error(), http.StatusInternalServerError)
+		return 0, model.NewAppError("SqlAuditStore.PermanentDeleteBatch", "store.sql_audit.permanent_delete_batch.app_error", nil, ""+err1.Error(), http.StatusInternalServerError)
 	}
 	return rowsAffected, nil
 }