Feature: #103563 - Add saving-related hotkeys to scheduler backend module 

See forge#103563

Description 

Similar to editing regular content elements, it is now possible to save scheduler tasks being edited via keyboard shortcuts as well.

Impact 

It is possible to invoke the Ctrl/Cmd + s hotkey to save a scheduler task, altogether with the hotkey Ctrl/Cmd + Shift + S to save and close a scheduler task.