date_format of string to time with "\n" has different behavior with MySQL

[mengxin9014]

Bug Report

Please answer these questions before submitting your issue. Thanks!

1. Minimal reproduce step (Required)

create table t (a char(32));
alter table t set tiflash replica 1;
insert into t values ("2022-02-01
16:33:00");
set tidb_enforce_mpp = 1;
select cast(a as datetime) from t;

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

+---------------------+
| cast(a as datetime) |
+---------------------+
| NULL                |
+---------------------+

3. What did you see instead (Required)

+----------------------+
| cast(a as datetime)  |
+----------------------+
| 2022-02-01 16:33:00  |
+----------------------+

4. What is your TiFlash version? (Required)

5.3.0