TiDB md5 result is different to MySQL

## Bug Report

Please answer these questions before submitting your issue. Thanks!

### 1. Minimal reproduce step (Required)

Using the test data from https://github.com/datacharmer/test_db

(Note: This is the sample data provided by MySQL https://dev.mysql.com/doc/employee/en/)

```
mysql --host 127.0.0.1 --port 4000 -u root < employees.sql
mysql --host 127.0.0.1 --port 4000 -u root -t < test_employees_md5.sql
```

### 2. What did you expect to see? (Required)

On MySQL 8.0:

```
mysql --host 127.0.0.1 --port 3306 -u root < employees.sql
mysql --host 127.0.0.1 --port 3306 -u root -t < test_employees_md5.sql
```

Result:

```
+----------------------+
| INFO |
+----------------------+
| TESTING INSTALLATION |
+----------------------+
+--------------+------------------+----------------------------------+
| table_name | expected_records | expected_crc |
+--------------+------------------+----------------------------------+
| departments | 9 | d1af5e170d2d1591d776d5638d71fc5f |
| dept_emp | 331603 | ccf6fe516f990bdaa49713fc478701b7 |
| dept_manager | 24 | 8720e2f0853ac9096b689c14664f847e |
| employees | 300024 | 4ec56ab5ba37218d187cf6ab09ce1aa1 |
| salaries | 2844047 | fd220654e95aea1b169624ffe3fca934 |
| titles | 443308 | bfa016c472df68e70a03facafa1bc0a8 |
+--------------+------------------+----------------------------------+
+--------------+------------------+----------------------------------+
| table_name | found_records | found_crc |
+--------------+------------------+----------------------------------+
| departments | 9 | d1af5e170d2d1591d776d5638d71fc5f |
| dept_emp | 331603 | ccf6fe516f990bdaa49713fc478701b7 |
| dept_manager | 24 | 8720e2f0853ac9096b689c14664f847e |
| employees | 300024 | 4ec56ab5ba37218d187cf6ab09ce1aa1 |
| salaries | 2844047 | fd220654e95aea1b169624ffe3fca934 |
| titles | 443308 | bfa016c472df68e70a03facafa1bc0a8 |
+--------------+------------------+----------------------------------+
+--------------+---------------+-----------+
| table_name | records_match | crc_match |
+--------------+---------------+-----------+
| departments | OK | ok |
| dept_emp | OK | ok |
| dept_manager | OK | ok |
| employees | OK | ok |
| salaries | OK | ok |
| titles | OK | ok |
+--------------+---------------+-----------+
+------------------+
| computation_time |
+------------------+
| 00:00:21 |
+------------------+
+---------+--------+
| summary | result |
+---------+--------+
| CRC | OK |
| count | OK |
+---------+--------+
```

### 3. What did you see instead (Required)

```
+----------------------+
| INFO |
+----------------------+
| TESTING INSTALLATION |
+----------------------+
+--------------+------------------+----------------------------------+
| table_name | expected_records | expected_crc |
+--------------+------------------+----------------------------------+
| departments | 9 | d1af5e170d2d1591d776d5638d71fc5f |
| dept_emp | 331603 | ccf6fe516f990bdaa49713fc478701b7 |
| dept_manager | 24 | 8720e2f0853ac9096b689c14664f847e |
| employees | 300024 | 4ec56ab5ba37218d187cf6ab09ce1aa1 |
| salaries | 2844047 | fd220654e95aea1b169624ffe3fca934 |
| titles | 443308 | bfa016c472df68e70a03facafa1bc0a8 |
+--------------+------------------+----------------------------------+
+--------------+------------------+----------------------------------+
| table_name | found_records | found_crc |
+--------------+------------------+----------------------------------+
| departments | 9 | d1af5e170d2d1591d776d5638d71fc5f |
| dept_emp | 331603 | 26f0a59726fef3d22f7f7fd872595a37 |
| dept_manager | 24 | 8720e2f0853ac9096b689c14664f847e |
| employees | 300024 | 4ec56ab5ba37218d187cf6ab09ce1aa1 |
| salaries | 2844047 | 892c9dfa133d6894fb7b66f2051b2103 |
| titles | 443308 | bfa016c472df68e70a03facafa1bc0a8 |
+--------------+------------------+----------------------------------+
+--------------+---------------+-----------+
| table_name | records_match | crc_match |
+--------------+---------------+-----------+
| departments | OK | ok |
| dept_emp | OK | not ok |
| dept_manager | OK | ok |
| employees | OK | ok |
| salaries | OK | not ok |
| titles | OK | ok |
+--------------+---------------+-----------+
+------------------+
| computation_time |
+------------------+
| 00:00:44 |
+------------------+
+---------+--------+
| summary | result |
+---------+--------+
| CRC | FAIL |
| count | OK |
+---------+--------+
```

### 4. What is your TiDB version? (Required)

```
Release Version: v7.6.0-alpha-390-ge1b50b2eed-dirty
Edition: Community
Git Commit Hash: e1b50b2eed78012b76bf6ddd4c2083b6d16dfd22
Git Branch: sql_calc_found_rows
UTC Build Time: 2023-12-11 06:16:06
GoVersion: go1.21.0
Race Enabled: false
Check Table Before Drop: false
Store: tikv
```