Migrate Storybook component stories to new format

[mimarz]

Use this script to auto-migrate the story, this helps you with the basis: https://storybook.js.org/docs/react/migration-guide#storiesmdx-to-mdxcsf.

You will still need to edit and adjust the files thereafter to get our desired result. Look at the stories of Accordion and Typography for inspiration.

Make a new issue + PR for each component when starting this cleanup

Checklist for new docs:

• Make sure "show code" show correct code.
• Make sure props table is interactive and works.
  • Have a look at Typography story for interactive props table on sub-components
• Do adjustments to types if needed
• Remove usages of TokenTable
• Add jsdocs to proptypes

### Tasks
- [ ] Migrate Textfield stories to new format
- [ ] https://github.com/digdir/designsystem/issues/369
- [ ] https://github.com/digdir/designsystem/issues/514
- [ ] https://github.com/digdir/designsystem/issues/581
- [ ] https://github.com/digdir/designsystem/issues/583

[mimarz]

Closing this as it will be solved as part of developing new updated version of the components for "felles designsystem".