Add VARCHAR/STRING length constraint information to the "Data type" column when used as an array type

**Is your feature request related to a problem? Please describe.**
When I make a VARCHAR(n)[] array type, I cannot see the length constraint in the "Properties" view -> "Columns" tab. It just shows `_varchar`.

**Describe the solution you'd like**
DBeaver should show `_varchar(n)` (CockroachDB shows it as `VARCHAR(n)[]` when running `SHOW COLUMNS FROM table`) when there's a length constraint applied to the type in the array.

**Additional context**
I'm using CockroachDB.