Increase font size in PDF

### Description

We need to increase the font size in the PDF in order to make it readable. 10 px (what we have now) is too small for most people, but increasing it might introduce breaking changes.

**Suggested approach:**
1. Test and find a sensible default size. @Edavda has some information about recommended sizes in Designsystemet.
2. Create a preview release with this sensible default.
3. Post the preview release in the Altinn Slack. Ask for feedback and that we are thinking of changing this. Encourage the TE to contact us if they think they'll have problems with the new size.
4. Wait for x amount of time (something pre-decided and written in the message described above ☝) and gather intelligence.
5. If no one reports any problems with the new size. Release it in production.
6. If anyone reports any problems, try to resolve them. A possible solution is to make the PDF font size configurable. In that case, discuss it with the team to find out the best place to put this configuration.
7. Release.

@Edavda please add or change anything you'd like!

**Suggested sizing**
I suggest starting with `small` and `Xsmall` sizes from the design system. These have been tested with other components and are sizes we are thinking about including in our app overall.

| Element | px size | pt size |
| -------- | ------- |------- |
| Paragraph small | 16 | 12
| Paragraph Xsmall | 14| 10,5
| Heading small | 24 | 18
| Heading Xsmall | 21 | 15,75

### In scope

_No response_

### Out of scope

_No response_

### Additional Information

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### Analysis

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### Conclusion

_No response_