App (integration) tests fail for fork PRs

[hggutvik]

Description of the bug

https://digdir.slack.com/archives/C0785747G6M/p1763120402032069

Steps To Reproduce

1. Create a fork of altinn-profile repo
2. Commit a change to the fork branch
3. Create a fork-PR to altinn-profile

Result: dotnet test fails (example)

Additional Information

Example of failing build&test workflow: https://github.com/Altinn/altinn-profile/actions/runs/19360399261/job/55390708418