[BUGFIX] Update display of start page field in "LinkValidator" task

In the "LinkValidator" scheduler task, you need to select a start page.
The button to select this page does not match the FormEngine markup.
which is fixed with this patch.

Resolves: #102462
Releases: main, 12.4
Change-Id: I213fde08a8a13bee462cdc3371514ce27c9e3e97
Reviewed-on: https://review.typo3.org/c/Packages/TYPO3.CMS/+/81926


Tested-by: core-ci <typo3@b13.com>
Tested-by: Christian Kuhn <lolli@schwarzbu.ch>
Reviewed-by: Christian Kuhn <lolli@schwarzbu.ch>