Replace it with the Help on Help command

Change-Id: Ia454a2f6a123b4fb68fda1eae1e07e99ba81487f
Reviewed-on: https://gerrit.libreoffice.org/29381Tested-by: Jenkins <ci@libreoffice.org>
Reviewed-by: Miklos Vajna <vmiklos@collabora.co.uk>