add tests for selection change and notify. usually, these hooks used for clipboard widget.
add tests for selection change and notify. usually, these hooks used for clipboard widget.

qtile/qtile,flacjacket/qtile,qtile/qtile,tych0/qtile,cortesi/qtile,tych0/qtile,ramnes/qtile,zordsdavini/qtile,flacjacket/qtile,soulchainer/qtile,frostidaho/qtile,zordsdavini/qtile,ramnes/qtile,soulchainer/qtile,frostidaho/qtile,cortesi/qtile