[Bug]: internal error: panic the `expr` must be integral constant expression when creating partition table with null value

### Is there an existing issue for the same bug?

- [X] I have checked the existing issues.

### Branch Name

main

### Commit ID

b2d8e4aefb0d7b3b3d7deb19a772c6bbfa973a9f

### Other Environment Information

```Markdown
- Hardware parameters:
- OS type:
- Others:
```

### Actual Behavior

mysql> CREATE TABLE t1 (a int) PARTITION BY RANGE(a) (PARTITION p0 VALUES LESS THAN (NULL));
ERROR 20101 (HY000): internal error: panic the `expr` must be integral constant expression:
github.com/matrixorigin/matrixone/pkg/sql/plan.getIntConstVal[...]
/Users/sudong/Program/MatrixOrigin/matrixone/pkg/sql/plan/partition_util.go:1024
github.com/matrixorigin/matrixone/pkg/sql/plan.getRangeValue
/Users/sudong/Program/MatrixOrigin/matrixone/pkg/sql/plan/partition_util.go:929
github.com/matrixorigin/matrixone/pkg/sql/plan.checkRangePartitionValue
/Users/sudong/Program/MatrixOrigin/matrixone/pkg/sql/plan/partition_util.go

### Expected Behavior

_No response_

### Steps to Reproduce

```Markdown
CREATE TABLE t1 (a int)
PARTITION BY RANGE(a)
(PARTITION p0 VALUES LESS THAN (NULL));
```

### Additional information

_No response_