fix wrong example code

Author: AllenFang

packages/react-bootstrap-table2-example/examples/column-filter/custom-filter-logic.js

@@ -12,11 +12,11 @@ import BootstrapTable from 'react-bootstrap-table-next';
 import filterFactory, { textFilter } from 'react-bootstrap-table2-filter';
 
 class Table extends React.Component {
-  filterByPrice = (filterVal) => {
+  filterByPrice = (filterVal, data) => {
     if (filterVal) {
-      return products.filter(product => product.price == filterVal);
+      return data.filter(product => product.price == filterVal);
     }
-    return products;
+    return data;
   }
 
   render() {