[BUGFIX] Use action icon instead of mimetype: actions-document-export-csv

Resolves: #69979
Releases: master
Change-Id: I3c11b4790a3784acaea4f6aeffbde6889e024c59
Reviewed-on: http://review.typo3.org/43440


Reviewed-by: Anja Leichsenring <aleichsenring@ab-softlab.de>
Tested-by: Anja Leichsenring <aleichsenring@ab-softlab.de>
Reviewed-by: Wouter Wolters <typo3@wouterwolters.nl>
Tested-by: Wouter Wolters <typo3@wouterwolters.nl>