Fix storybook live demo url (#1366)

Author: CYBAI

packages/react-bootstrap-table2-filter/README.md

@@ -2,7 +2,7 @@
 
 `react-bootstrap-table2` separate the filter core code base to [`react-bootstrap-table2-filter`](https://github.com/react-bootstrap-table/react-bootstrap-table2/tree/develop/packages/react-bootstrap-table2-filter), so there's a little bit different when you use column filter than `react-bootstrap-table`. In the following, we are going to show you how to enable the column filter:
 
-**[Live Demo For Column Filter](https://github.com/react-bootstrap-table/react-bootstrap-table2/blob/gh-pages-src/storybook/index.html?selectedKind=Column%20Filter)**
+**[Live Demo For Column Filter](https://react-bootstrap-table.github.io/react-bootstrap-table2/storybook/index.html?selectedKind=Column%20Filter)**
 
 **[API&Props Definitation](https://react-bootstrap-table.github.io/react-bootstrap-table2/docs/filter-props.html)**
 
@@ -385,4 +385,4 @@ export default () => (
     />
   </div>
 );
-```
+```