[lib] Delete the old universalCommunityPermissions set

Summary:
Now that I'm ready to land the stack for fixing thread permissions, I can safely remove the old universalCommunityPermissions set since we now have a function that takes in a thread type and returns back a blob of universal community permissions accordingly.

Also took this time to quickly remove the unit tests that had previously hard-coded user-surfaced permissions for two reasons:

• we now have a list defined in thread-permissions
• we just do not need this unit test because now, since constructing member blobs for communities uses user-surfaced permissions, this unit test doesn't test anything of importance

Depends on D9945

Test Plan: Ran yarn workspace lib test and flow to make sure I covered all instances of the old universalCommunityPermissions

Reviewers: atul, ginsu, ashoat

Reviewed By: ashoat

Subscribers: tomek

Differential Revision: https://phab.comm.dev/D9953