Remove `interop:AccessAuthorization`, `interop:AccessGrant` and `interop:AccessNeedGroup`

From Friday meeting with @elf-pavlik:

• SR: Are Access Authorizations and Access Grants really needed ? It seems they are used only to group together grants/authorizations, but it's a lot of work to manage them. Similarly it seems we could do without Access Need Groups.
• SR: IMO if we can simplify some parts of SAI, it will increase adoption amongst developers.
• SR: For me data authorizations/grants are the basis of SAI permission system. We can do a lot with them. Access authorizations/grants just seem an annoyance. We could link data grants directly from application registration or social agent registrations.
• eP: Original purpose was to group together grants. This reduces the number of time a agent registration is updated.
• SR: In ActivityPods, we update the registration only when all data grants have been updated.
• eP: Was also used to group together access needs, so that they could be accepted together.
• SR: Maybe an optional predicate could identify AccessNeeds which should be "grouped" ?
• eP: I will contact Justin and Eric to see if there are use cases I don't remember about.