How do you turn on the new 'Shared Voicemail Inbox' feature in the iPhone app?

The new Shared Voicemail Inbox feature is included in the recent RingCentral iPhone app update (23.1.30).

It's indicated in the "What's New" update notes that if a coworker "gives you access" to their voicemail, their voicemail messages will show up in the Shared Voicemail Inbox.

However I see nothing in the settings for the desktop or smartphone app whereby I can give access to my voicemail (or Shared Voicemail Inbox) to a coworker.

Please advise...