fix: Make call to updateMetamaskNotificationsList async and fix its event emission.

[hmalik88]

Explanation

• What is the current state of things and why does it need to change? The updateMetamaskNotificationsList function is async and the registered message handler should also have been async. The NotificationServicesController:notificationsListUpdated event is not being received by the extension.
• What is the solution your changes offer and how does it work? Make the message handler async and move the publish call outside of the update function.
• Are there any changes whose purpose might not obvious to those unfamiliar with the domain? This problem was never uncovered because the updateMetamaskNotfiicationsList function was never called in the extension until now (with snaps). When triggering a notification, with the current state of things, the extension would not update the badge counter because it wasn't receiving the NotificationServicesController:notificationsListUpdated event.

Changelog

@metamask/notification-services-controller

• FIXED: updateMetamaskNotificationsList was fixed by updating the message handler and moving the publish call outside of the update to state in the function.

Checklist

• I've updated the test suite for new or updated code as appropriate
• I've updated documentation (JSDoc, Markdown, etc.) for new or updated code as appropriate
• I've highlighted breaking changes using the "BREAKING" category above as appropriate
• I've prepared draft pull requests for clients and consumer packages to resolve any breaking changes