Buttons with actions tied to an autoexclusive group can be unchecked by clicking again

if a series of buttons is tied to actions that belong to an autoexclusive group, they work correctly as kinda "radiobuttons", clicking on a new one unselects the current one, but when clicking again on the selected one, it unselects it, making no actions selected in the group, which is not the correct behavior for a radiobutton-like scenario.

Attached a test case with two toolbuttons  where is possible to unselect by clicking again