[lib] Add store migration for CREATE_SIDEBAR and SIDEBAR_SOURCE message

Test Plan:
Performed two tests:

1. With codeVersion=74, logged out, logged in and checked if the messages were unshimmed (this tests unshimMessageInfos)
2. With codeVersion=74, removed message types from localUnshimTypes, checked if shimmed message was displayed. Then increased store version, restarted the app and checked if messages were unshimmed (this tests unshimMessageStore)

Reviewers: ashoat

Reviewed By: ashoat

Subscribers: KatPo, zrebcu411, Adrian, atul, subnub

Differential Revision: https://phabricator.ashoat.com/D664