Add All Task Assignees to the Task Completion to Task Dependents Email Notification

[#1]

Under the "Information about Work Assigned to Me" in notification settings, there's a notification called "A predecessor of one of my tasks is completed".

This notification sends to all task assignees, but only puts the primary task owner's name in the email as being assigned to the task.

This is confusing for task assignees who aren't the primary owner because they get the email saying a predecessor of their task is completed, but it doesn't say their name by the task they're assigned to.

All task assignees should be listed in the email notification.