[BUGFIX] Uploading CSV file fails in importer

Uploading CSV or inputing CSV data fail in the importer.
This corrected the uploading of the CSV, since 6.2 uses FAL
for file handling

Resolves: #59342
Releases: 4.0
Change-Id: Ia6ab1032b295b6c2cf63eb11bbd917d0c9255c3d
Reviewed-on: https://review.typo3.org/30565
Reviewed-by: Ivan Dharma Kartolo
Tested-by: Ivan Dharma Kartolo