DuckDB support tries to make primary columns with type SERIAL, then crashes

`orm.yaml`:

```yaml
tables:
  mytable:
    mycolumn:
      primary: true
      type: INTEGER
```

Then `datafaker create-tables`:

```
ProgrammingError: (_duckbd.CatalogException) Catalog Error: Type with name SERIAL does not exist!
Did you mean "JSON"?
[SQL:
CREATE TABLE "mytable" (
        "mycolumn" SERIAL,
        PRIMARY KEY ("mycolumn")
)
]
```