So that the UI can show the correct "Signed by" and "Digital ID issued
by" fields.

Change-Id: Ied2fed480f48baf60cffb4f0ce762a726beab006
Reviewed-on: https://gerrit.libreoffice.org/29776Tested-by: Jenkins <ci@libreoffice.org>
Reviewed-by: Miklos Vajna <vmiklos@collabora.co.uk>