[lib] Rename RelationshipRequest to TraditionalRelationshipRequest

Summary:
This is just a straightforward rename. Will want a separate name for the type of RelationshipRequest that includes userIDs vs userIDsToFID. Initially went with RelationshipRequestSansFarcaster or something like that, but thought TraditionalRelationshipRequest might be better?

This diff is just rename, the type will be updated so action is typed as RelationshipActionSansFarcaster

Test Plan: NA, flow, just a rename

Reviewers: varun, ginsu, tomek, will

Reviewed By: ginsu

Subscribers: ashoat

Differential Revision: https://phab.comm.dev/D11602