fdo#57950: Remove chained appends in accessibility

Change-Id: I4ba583a891933068ab4003307d09693180c7b61f
Reviewed-on: https://gerrit.libreoffice.org/7436
Reviewed-by: Noel Grandin <noelgrandin@gmail.com>
Tested-by: Noel Grandin <noelgrandin@gmail.com>