Bumped Pagerfanta link (#3291)

Author: mnocon

docs/search/search_api.md

@@ -259,7 +259,7 @@ Pagination can then be rendered for example using the following template:
 [[= include_code('code_samples/api/public_php_api/templates/themes/standard/full/custom_pagination.html.twig') =]]
 ```
 
-For more information and examples, see [PagerFanta documentation](https://www.babdev.com/open-source/packages/pagerfanta/docs/2.x/usage).
+For more information and examples, see [PagerFanta documentation](https://www.babdev.com/open-source/packages/pagerfanta/docs/3.x/usage).
 
 #### Pagerfanta adapters