fdo#81218 - update Copyright year in DEB files

Change-Id: Id8d83c09535e79146d65d615e85f0f18535b95d5
Reviewed-on: https://gerrit.libreoffice.org/10223
Reviewed-by: Caolán McNamara <caolanm@redhat.com>
Tested-by: Caolán McNamara <caolanm@redhat.com>