message: [CI] add buster backports in CI builder setup
  CI builder is bumped to debian:buster in but it missed
  the backports to keep the tooling packages consistent with the
  Docker build.
  Closes:
  Approved by: davidiw
diff: @@ -44,6 +44,7 @@ commands:
  - run:
  name: Install Dependencies
  command: |
  + sudo sh -c 'echo "deb http://deb.debian.org/debian buster-backports main" > /etc/apt/sources.list.d/backports.list'
  sudo apt-get update
  sudo apt-get install -y cmake curl
  sudo apt-get clean
  