revert not needed changes

packages/react-bootstrap-table2-example/examples/row-expand/non-expandable-rows.js

@@ -25,7 +25,6 @@ const expandRow = {
       <p>expandRow.renderer callback will pass the origin row object to you</p>
     </div>
   ),
-  showExpandColumn: true,
   nonExpandable: [1, 3]
 };
 
@@ -51,7 +50,6 @@ const expandRow = {
       <p>expandRow.renderer callback will pass the origin row object to you</p>
     </div>
   ),
-  showExpandColumn: true,
   nonExpandable: [1, 3]
 };