MDEV-38694 Do not override false use_parallel when select_lex has aggregate function in determining pre call

TODO: improve commit message

Author: mariadb-YuchenPei

sql/ha_partition.cc

@@ -6193,8 +6193,7 @@ int ha_partition::common_first_last(uchar *buf)
     return error;
   if (!m_ordered_scan_ongoing)
   {
-    if (unlikely((error= handle_pre_scan(reverse_order,
-                                         check_parallel_search()))))
+    if (unlikely((error= handle_pre_scan(reverse_order, FALSE))))
       return error;
     return handle_unordered_scan_next_partition(buf, reverse_order);
   }

storage/spider/ha_spider.cc

@@ -8309,7 +8309,8 @@ void ha_spider::check_pre_call(
       select_lex, &select_limit, &offset_limit);
     if (
       select_lex &&
-      (!select_lex->limit_params.explicit_limit || !select_limit)
+      (!select_lex->limit_params.explicit_limit || !select_limit) &&
+      !select_lex->with_sum_func
     ) {
       use_pre_call = TRUE;
     }