EM: can't navigate outdated extension pages

Env

• XWiki 18.4.5 / 18.4.1, xjetty, mariadb
• More than 5 outdated extensions

Issue

When checking for updates, only the first 5 extensions are displayed.
If you click on another page number, or if you use the arrows to change page, the content reset back to the "check for update" button.

Impact

The feature doesn't work as intended. A user can't navigate through its outdated extension, to review the list, or update a particular one (without searching for it in the extension search).