[BUGFIX] Only call getMovePlaceholder for MOVE_POINTER records

Since isInWebMount now calls BEgetRootline with workspace overlays,
an additional query for ALL requested pages in rootline is made, because
getMovePlaceholder() is called every time and does not know the
actual record - getMovePlaceholder should only be called on MOVE_POINTER
records.

An additional check makes the Page tree work again for editors in workspaces.

Resolves: #91360
Releases: master, 9.5
Change-Id: I1822a9824a0c9aacf4f3e1a900cbd19bd95ed9b9
Reviewed-on: https://review.typo3.org/c/Packages/TYPO3.CMS/+/64453


Tested-by: Achim Fritz <af@achimfritz.de>
Tested-by: TYPO3com <noreply@typo3.com>
Tested-by: Benni Mack <benni@typo3.org>
Reviewed-by: Achim Fritz <af@achimfritz.de>
Reviewed-by: Oliver Hader <oliver.hader@typo3.org>
Reviewed-by: Benni Mack <benni@typo3.org>