Allow scheduled sync task to be updated when it has been edited.

[AllanOXDi]

Observed behavior

Currently, when a user edits a scheduled sync task, a new task is created instead of updating the existing one. This creates confusion.

Expected behavior

When a user edits a scheduled sync task, the changes should be applied to the existing task instead of creating a new task.

User-facing consequences

This issue affects users who create and manage scheduled sync tasks. By allowing tasks to be updated when edited, users will have a more streamlined experience as they manage their tasks more efficiently.

Context

It is a follow up issue from sync schedule work #9786