Support for Aksel-icons in components

We need to find a good solution for allowing users to decide what icons to use in our components. It should be possible to pick an icon from the [Aksel's Icon library](https://aksel.nav.no/ikoner) to be displayed in various components.

### Limitations
We suggest allowing only icons from Aksel for now. The possibility of adding other icon libraries or custom icons need to be discussed. The Aksel Icon library is recommended by the design system.

Start by reviewing the existing component APIs and the linked Aksel Icon library to identify which components need icon support. The issue names no files or tests, so first establish the affected components and the intended configuration boundary. Done means the agreed Aksel icons can be selected and displayed consistently in the relevant components.

Written by the indexing model from the issue text.