[lib] [1/n] add UserSettingsRequest action

Summary: Add User Setting action for user default notification settings

Test Plan: N/A just a small piece of the redux life cycle

Reviewers: atul, ashoat, palys-swm

Reviewed By: ashoat

Subscribers: palys-swm, Adrian, karol-bisztyga, boristopalov

Differential Revision: https://phabricator.ashoat.com/D2331