[CBRD-24638] The problem of the default value of column when altering the type of column.

[beyondykk9]

http://jira.cubrid.org/browse/CBRD-24638

The problem is that the type of the column is changed, but the type of the default value is not changed. An error occurs while reading the default value in the format of the column type, not the stored type.

CREATE TABLE t_def (a bigint default 123456789012, b varchar(20));
ALTER TABLE t_def a a int;

Expected:
    ERROR: A domain conflict exists on attribute "a".

Actual:
    no error