DAYOFMONTH returns NULL in SELECT but evaluates as FALSE in WHERE clause for certain input

## Bug Report

### 1. Minimal reproduce step (Required)
```sql
CREATE TABLE t(c VARCHAR(500));
INSERT INTO t VALUES ('a');

SELECT DAYOFMONTH(-t.c) FROM t WHERE NOT DAYOFMONTH(-t.c); -- NULL
```
### 2. What did you expect to see? (Required)

Empty or 0, MySQL output empty for this query.

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

Null

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

```
tiup playground nightly --host 0.0.0.0 --kv 3 --tiflash 3
```
```
8.0.11-TiDB-v9.0.0-beta.2.pre-384-g5fab436
```