[BUG]: getTableConfig primaryKeys doesn't return all primary key columns

### What version of `drizzle-orm` are you using?

0.28.6`

### What version of `drizzle-kit` are you using?

_No response_

### Describe the Bug

When using `getTableConfig()`, the `primaryKey` attribute doesn't return any columns where the primary key was referenced in the column vs in the table.

```ts
const table = pgTable({
id: varchar("id").primaryKey()
})

const {primaryKey} = getTableConfig(table); // primaryKey is an empty array

const table2 = pgTable({
id: varchar("id")
}, (table) => {
pk: primaryKey(table.id)
})

const {primaryKey} = getTableConfig(table2); // primaryKey has 1 item
```

### Expected behavior

I expect the `primaryKey` array to have all primary key columns.

### Environment & setup

_No response_