Always show notifications bell

[PVince81]

Regardless whether notifications are available or not, always display the bell.

When clicked, if no notifications, show a message in the dropdown that says so.

I guess we should still visually change the bell whenever notifications exist, like adding a small number ?

@pmaier1

[pascalwengerter]

@tbsbdr should we implement this?

[tbsbdr]

yes

[kulmann]

yes

#8450 😁