Adwaita: Fix active spinbutton button image color

Adwaita: Fix active spinbutton button image color

The spinbutton>button>image is currently blue when the image is clicked
and dark-ish when the button is clicked(but not the image). This was not
the case before since we didn't even propagate :active down to the image
child. Fix this by only applying the blue color to direct image children
of entries.