Feature: #12211 - Usability: Scheduler provide page browser to choose start page

See forge#12211

Description

To improve the usability of the linkvalidator scheduler task, the page browser is provided to choose the start page.

Impact

Scheduler tasks that need a page uid can now add a button for the page browser popup.

In the ValidatorTaskAdditionalFieldProvider two additional fields have to be added.

'browser' => 'page',

If the additional field browser is set to page then the SchedulerModuleController adds a button for calling the page browser popup to the field.

'pageTitle' => $pageTitle,

The pageTitle contains the title of the page that is shown next to the browse button.