issue with typography layer order

[Barsnes]

First reported in #2580, and moved here to keep issues focused to one thing.

From @vaarvik:

However, I also experienced a bug with the typography styles when adding my own theme. Basically the issue was that typography got the wrong font size. I had to add the following @layer styles to change the the priority for ds.theme.typography.* (in my generated theme.css) to be higher than the ds.base.typography (from designsystemet/css):

@layer ds.base, ds.theme;