[lib] introduced rawMessageInfoFromMessageData function to reaction message spec

Summary:
introduced rawMessageInfoFromMessageData function to reaction message spec. rawMessageInfoFromMessageData converts the ReactionMessageData into a RawReactionMessageInfo

Depends on D5690
Linear Task: ENG-2245

Test Plan: Ran web and mobile app locally and nothing crashes/will be doing more tests on this message spec in subsequent diffs

Reviewers: atul, tomek, rohan

Reviewed By: atul, tomek, rohan

Subscribers: ashoat, tomek, atul

Differential Revision: https://phab.comm.dev/D5804