fix(checkbox): dont show visual changes on disabled checkboxes

When any checkbox variant was disabled, it was still showing visual changes on hover which would indicate a possibility to change the checkbox (although greyed out and not possible)

Author: lubber-de

src/definitions/modules/checkbox.less

@@ -353,6 +353,7 @@
     cursor: default !important;
     opacity: @disabledCheckboxOpacity;
     color: @disabledCheckboxLabelColor;
+    pointer-events: none;
   }
 }