bug(permissions): handle DL / group emails for the permissions

[zereraz]

As of now we don't handle permissions correctly for distribution list or group emails in google workspace.
Example: legal@xynehq.com we would put as is.

We need to add support for this in the permission aware RAG.

We would probably need these permissions

https://www.googleapis.com/auth/admin.directory.group.readonly
https://www.googleapis.com/auth/admin.directory.group.member.readonly

Then we keep syncing it.

Edge case:

• If someone is removed or added to a group mail, how to know what files to update the permission to. This has perf implications too
• Since we use Set for permissions, what if group email is removed but a user part of the group email still has access to a doc.