BUG: Fix lost on focus when modifying spinbox

Previously, the spinbox would lose focus when modifying the value due to
an update by the node. Using the new ctkSpinBox that actually checks
if the values are the same before updating fixes this.

See Issue #2986

git-svn-id: http://svn.slicer.org/Slicer4/trunk@21902 3bd1e089-480b-0410-8dfb-8563597acbee