The automation feature in Shortcut app allows us to start Do Not Disturb (DND) mode when iPhone is connected to a charger and turn it off when the charger is disconnected. Since I usually charge my phone while working or sleeping, this is a very comfortable way to reduce disruptions and to prevent forgetting to turn DND off later.
An automation send us a notification when it is executed, i.e., every time when we charge a phone. Unfortunately, Shortcut app notifications can't be turned off from the settings screen. But for some reason, we can can turn off this notification by modifying it from Screen Time (though it seems like a bug in iOS).
Update on 21.01.2021:
Apple fixed this bug on iOS 14.3. We are no longer able to turn off notifications from the Shortcut app.