The logic for building `userPushInfoPromise` will be really simlar when we build `userRescindInfoPromise` so I built `generateNotifUserInfoPromise` to reuse this logic in a subseqent diff
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Depends on D6307
Linear Task: [[ https://linear.app/comm/issue/ENG-2644/rescind-a-reaction-message-notif-with-a-remove-action-from-the | ENG-2644 ]]