"show status like" is not case insensitive

Bug Report

Please answer these questions before submitting your issue. Thanks!

1. Minimal reproduce step (Required)

show status like 'ssl_cipher';

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

mysql> show status like 'ssl_cipher';

+---------------+-------+
| Variable_name | Value |
+---------------+-------+
| Ssl_cipher    |       |
+---------------+-------+
1 row in set (0,00 sec)

3. What did you see instead (Required)

tidb> show status like 'ssl_cipher';

Empty set (0,00 sec)

show status like 'Ssl_chipher'; works.

4. What is your TiDB version? (Required)

tidb_version(): Release Version: v5.2.0-alpha-272-g88cbdecc5
Edition: Community
Git Commit Hash: 88cbdecc58437619a0dd1c5554be20d079971978
Git Branch: master
UTC Build Time: 2021-07-14 13:23:50
GoVersion: go1.16.2
Race Enabled: false
TiKV Min Version: v3.0.0-60965b006877ca7234adaced7890d7b029ed1306
Check Table Before Drop: false

MySQL has case insensitive match for LIKE of status and variables, where TiDB seems to have case sensitive matching of LIKE operator. I also tried with both options for:

tidb> SELECT VARIABLE_VALUE FROM mysql.tidb WHERE VARIABLE_NAME='new_collation_enabled';

+----------------+
| VARIABLE_VALUE |
+----------------+
| True           |
+----------------+
1 row in set (0,00 sec)