Unexpected behavior for `case when {false condition} then {subquery...} else {...} end`
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Description
## Bug Report
Please answer these questions before submitting your issue. Thanks!
ref #34217
### 1. Minimal reproduce step (Required)
```
DROP TABLE IF EXISTS t1;
DROP TABLE IF EXISTS t2;
create table t1(c1 int);
insert into t1 values(2), (3);
select * from t1 where (case when 0 <> 0 then (select c1 from t1) else 0 end) > 1;
explain select * from t1 where (case when 0 <> 0 then (select c1 from t1) else 0 end) > 1;
select * from t1 where (case when (select count(1) from t1) = 0 then (select c1 from t1) else 0 end) > 1;
```
### 2. What did you expect to see? (Required)
MySQL
```
mysql> select * from t1 where (case when 0 <> 0 then (select c1 from t1) else 0 end) > 1;
Empty set (0.00 sec)
```
### 3. What did you see instead (Required)
```
MySQL [test]> select * from t1 where (case when 0 <> 0 then (select c1 from t1) else 0 end) > 1;
ERROR 1242 (21000): Subquery returns more than 1 row
MySQL [test]> explain select * from t1 where (case when 0 <> 0 then (select c1 from t1) else 0 end) > 1;
ERROR 1242 (21000): Subquery returns more than 1 row
MySQL [test]> select * from t1 where (case when (select count(1) from t1) = 0 then (select c1 from t1) else 0 end) > 1;
ERROR 1242 (21000): Subquery returns more than 1 row
```
### 4. What is your TiDB version? (Required)
>= release-4.0
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