[BUGFIX] Failing Unit test in FAL LocalDriver

Issue #42603 changed the default behavior of the Driver systems
to also show hidden directories by default. This should be
reflected in the unit test with flipping the logic of one test
that actually tested the opposite and fails now.

Change-Id: I93492f2ec213423ffa06339f6a63de494d544534
Fixes: #42230
Related: #42603
Releases: 6.0
Reviewed-on: http://review.typo3.org/16105
Reviewed-by: Steffen Ritter
Tested-by: Steffen Ritter
Reviewed-by: Christian Kuhn
Tested-by: Christian Kuhn