Front end error when using datamodel type "Kombinasjon" on top level with type "one_of"

### Description of the bug

When having a datatype "Kombinasjon" and using "one_of" on the top level in the datamodel the frontend presents error messages.


Link to Slack thead https://altinn.slack.com/archives/C02EJ9HKQA3/p1717418871792039

Please note that I have not pinpointed exactly what combinations that fail.

Form with the issue: https://altinn.studio/repos/srf/anmodning-kapitalkonto (NB: We have changed the form after the issue, so you need to revert to https://altinn.studio/repos/srf/anmodning-kapitalkonto/commit/61317cc04e8a8940557d2ab9210fad47870deb9f for having the error)

### Steps To Reproduce

* Create a form
* Add a type "Kombinasjon" on top level using "one_of"
* Use that datamodel reference on a field in the form
* Open the form and observe the error message.

### Additional Information

_No response_

Revert the anmodning-kapitalkonto form to commit 61317cc04e8a8940557d2ab9210fad47870deb9f and reproduce the error using a top-level Kombinasjon type with one_of. Trace the frontend failure from the affected datamodel field; done means the form opens without the reported error for the failing combination.

Written by the indexing model from the issue text.