[AC-1288] Move AssociationWithPermissions public api model to AC Team

[eliykat]

Type of change

- [ ] Bug fix
- [ ] New feature development
- [x] Tech debt (refactoring, code cleanup, dependency upgrades, etc)
- [ ] Build/deploy pipeline (DevOps)
- [ ] Other

Objective

The AssociationWithPermissions model is used to upsert CollectionUser or CollectionGroup associations via the Public API. It goes to OrganizationUser/Group permissions, so should be owned by AC Team. (Or arguably Vault, but I already discussed with @shane-melton and we agreed it could live with AC at least for now.)

I'm not sure why it's currently owned by Auth, maybe it was just scooped up with other file moves? Happy to discuss if there are any queries/issues here.

Code changes

• file.ext: Description of what was changed and why

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