connectivity: Use chain of .append methods

Change-Id: I15604e97dc38f1fcfa62c3d86208e72a86dda23e
Reviewed-on: https://gerrit.libreoffice.org/11688
Reviewed-by: Noel Grandin <noelgrandin@gmail.com>
Tested-by: Noel Grandin <noelgrandin@gmail.com>