Add Setting in Mail App to Disable Calendar Notifications

[wrdhub]

User story: I don't want double notifications for calendar events if I have the Calendar and mail app installed.

AC:

• A per user, per device setting on the mail app
• "Receive calendar event notifications?" → a yes/no toggle
• When this setting is "no", if notifications are active for that app, mail notifications are received but calendar notifications are not
• When this setting is "yes", if notifications are active for that app, mail notifications and calendar notifications are received
• When notifications are not active for that app, this option shows but is grayed out (and set to no)
• When this setting is changed to "no", calendar event notifications that have been scheduled should be unscheduled and no future events should be notified.
• When this setting is changed to "yes", calendar events with existing notifications on them should be rescheduled and send when applicable.

Test notes

On Mail mobile app:

• In the settings page there's a new select field to control if Mail app should receive calendar notifications/alarms.
• If the settings is active nothing should change, and all notifications should arrive.
• If it is disabled, only email notifications should appear for the mail app.
• Calendar app, Desktop client and Webapp shouldn't be affected by this setting.