Profile gets cached in App instance for 9 minutes

### Description of the bug

This is a problem, because a user might want to change language (because of us making similar mistakes as in https://github.com/Altinn/app-frontend-react/pull/610), and suddenly the language is inconsistent and different between apps and app instances.

### Steps To Reproduce

1. Open an app.
2. Go back to the inbox and change language
3. Visit the app again
4. It's a coin toss if the language was really changed.

### Additional Information

_No response_

Start by tracing where the profile is cached in the App instance and reproduce the language change using the listed steps. Confirm that revisiting the app after changing language no longer returns a stale profile and that language remains consistent between apps and app instances.

Written by the indexing model from the issue text.