tests: Fix test of non-canonical permissions
tests: Fix test of non-canonical permissions

When installing via the child repo we now strip the permissions early
so the import will fail instead of import and then canonicalize.
Either is ok, as nothing should be non-canonical in real life.

Closes: #2657
Approved by: alexlarsson

flatpak/flatpak,matthiasclasen/flatpak,flatpak/flatpak,matthiasclasen/flatpak,flatpak/flatpak,flatpak/flatpak,matthiasclasen/flatpak,matthiasclasen/flatpak,matthiasclasen/flatpak,flatpak/flatpak