[TASK] Use function for temp. page tree in BrowseLinks too

The new introduced function ElementBrowser::getTemporaryTreeMountCancelNotice()
shall also be used in its subclass to remove code duplication.

Resolves: #56666
Releases: 6.2
Change-Id: I0d7aca1c0695479f7ced9323098c0e7b04f1abda
Reviewed-on: https://review.typo3.org/28179
Reviewed-by: Markus Klein
Tested-by: Markus Klein