LB_BACKPORTS missing apt '-t backports'

[Alexey Kuznetsov]

Hello!

'lb config --backports true' does not automatically install recent
backports packages, additional configuration required:

'lb config --apt-options "-t bookworm-backports --yes"

I guess build/functions/configuration.sh missing line after:
APT_OPTIONS="${APT_OPTIONS:---yes -o Acquire::Retries=5}"

if [ "${LB_BACKPORTS}" != "true" ] && [ "${LB_BACKPORTS}" != "false" ];
then
  APT_OPTIONS="$APT_OPTIONS -t $LB_DISTRIBUTION-backports"
fi

-- AK