Add django-import-export integration to admin-index?

[alextreme]

I know we can use fixtures, however being able to export/import the applicationgroup configuration to/from CSV and JSON would allow admin-users to easily copy over configuration between test/staging/production environments.

I suspect a hard dependency on django-import-export wouldn't be acceptable, but I suspect we could make it optional and automatically use it if installed

[sergei-maertens]

doesn't seem too far fetched to have an django-admin-index[import-export] dependency group

however - django-import-export typically exports per table and I'm not sure it can properly handle the relations between appgrouop and link/app group item 🤔