[native] Redux migration to remove messageStore.threads[threadID].[lastPruned/lastNavigatedTo]

Summary:
Redux migration to remove messageStore.threads[threadID].[lastPruned/lastNavigatedTo].

We don't **really* need this since messageStore.threads is persisted by both Redux and SQLite so the SQLite SET_MESSAGE_STORE will override the messageStore.threads that were REHYDRATED as soon as the app is first opened anyways, but figure it doesn't hurt.

Depends on D9517

Test Plan: messageStore.threads looks as expected after migration completes.

Reviewers: ashoat, tomek, rohan, ginsu

Reviewed By: ashoat

Subscribers: wyilio

Differential Revision: https://phab.comm.dev/D9518