[FEATURE] Test field for Akismet

Resolves: #59247
Releases: 6.2
Change-Id: I228fcb15a2a25fbf73aa67adfd8df2656a5c5fe0
Reviewed-on: http://review.typo3.org/33311
Reviewed-by: Ralf Zimmermann <ralf.zimmermann@tritum.de>
Tested-by: Ralf Zimmermann <ralf.zimmermann@tritum.de>