TreeTable filter demo not working

The TreeTable filter demo throws an error when any input is entered.

To recreate: Navigate to "/showcase/#/treetable/filter". Enter any text in any search or filter edit.

Result: 
```
TypeError: Cannot read property 'type' of undefined
    at Proxy.columnProp (app.bbd570d8.js:1)
...
```
and further rendering fails.

PrimeVue 3.3.2 on Vue 3 by PrimeTek
