[Bug]: clone subscription takes too long compared with non-subscriptions.

### Is there an existing issue for the same bug?

- [x] I have checked the existing issues.

### Branch Name

main, 3.0

### Commit ID

latest

### Other Environment Information

```Markdown
- Hardware parameters:
- OS type:
- Others:
```

### Actual Behavior

Clone subscription took too long compared with non-subscriptions.

```
mysql>
mysql> show subscriptions;
+----------+-------------+--------------+------------+-------------+---------------------+----------+---------------------+--------+
| pub_name | pub_account | pub_database | pub_tables | pub_comment | pub_time | sub_name | sub_time | status |
+----------+-------------+--------------+------------+-------------+---------------------+----------+---------------------+--------+
| pubg | sys | dbg | * | | 2025-12-15 09:41:30 | test | 2025-12-15 09:43:03 | 0 |
+----------+-------------+--------------+------------+-------------+---------------------+----------+---------------------+--------+
1 row in set (0.082 sec)

mysql> show tables from test;
+----------------+
| Tables_in_test |
+----------------+
| t1 |
| t10 |
| t2 |
| t3 |
| t4 |
| t5 |
| t6 |
| t7 |
| t8 |
| t9 |
+----------------+
10 rows in set (0.295 sec)

mysql> create database test3 clone test;
Query OK, 0 rows affected (6.329 sec)

```

### Expected Behavior

_No response_

### Steps to Reproduce

```Markdown
see above
```

### Additional information

_No response_