[BUGFIX] FAL readonly: Directory copying results in BE exception

Changed parent class of folder permission exceptions to
InsufficientFolderAccessPermissionsException so excecption
could be catched properly.

Change-Id: I1c85e4c0e4652f1e3394fd58f98d95ea6ca8cc34
Resolves: #56494
Releases: 6.2
Reviewed-on: https://review.typo3.org/27994
Reviewed-by: Christian Weiske
Tested-by: Christian Weiske
Reviewed-by: Wouter Wolters
Tested-by: Wouter Wolters