feat: passing fcmToken when using mobile

[Jonathansoufer]

Explanation

This PR adds support to FCM Token to be passed as an optional param when using mobile platform since mobile handle FCM Token creation natively through Firebase SDK.

References

NOTIFY-1240

Changelog

@notification-services-controller

ADDED: optional FCM token to use for push notifications on enablePushNotifications

Checklist

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