[lib/native/web] update getMessageLabel parameters

Summary:
Small refactor diff so that we can use getMessageLabel in a subsequent diff. In this subsequent diff we will use this function, but we will only have access to the threadID from the messageInfo. Since we are only using the threadID in this function, it seems better to only pass the threadID instead of the whole threadInfo

Depends on D8628

Test Plan: flow and everything still works as expected

Reviewers: atul, kamil

Reviewed By: atul

Subscribers: ashoat, tomek

Differential Revision: https://phab.comm.dev/D8629